Cargo.toml

@@ -1,5 +1,5 @@
 [package]
-name = "fastwave_backend"
+name = "fastwave"
 version = "0.1.0"
 edition = "2021"
 
@@ -10,7 +10,7 @@ debug = 1
 
 [dependencies]
 num = "0.4"
-clap = { version = "4.4.6", features = ["derive"] }
+clap = { version = "3.1.8", features = ["derive"] }
 chrono = "0.4"
 # TODO : remove itertools once date parser is reworked.
-itertools = "0.11"
+itertools = "0.10.3"

LICENSE-YEHOWSHUA

@@ -1,2 +0,0 @@
-This codebase is also licensed to Yehowshua Immanuel to use
-in any manner Yehowshua Immanuel sees fit.

README.md

@@ -1,24 +1,7 @@
-Copyright(2023) - Yehowshua Immanuel
-
-# Vision
-Imagine being able to visualize a CPU pipeline diagram by merely loading a simulation waveform dump, sprinkling in a bit of code, and dragging and dropping some diagram blocks into the visualizer. This project aims to offer such an experience.
-
-Since this project is written in Rust, it should also be able to run in the browser via web-assembly.
-
-# Status
-As of January 2024, work on the Fastwave Backend is stalled. It has been a fun journey watching Fastwave enable the first iterations of the [surfer waveform viewer](https://surfer-project.org). Now surfer uses an even better backend called [Wellen](https://github.com/ekiwi/wellen?tab=readme-ov-file). Go check it out! I hear it's really good. Perhaps I will soon archive the Fastwave Backend.
-
-Browser demo: https://app.surfer-project.org/
-
-Screenshot of surfer frontend below:
-<img width="1609" alt="image" src="https://github.com/ThePerfectComputer/FastWaveBackend/assets/103011002/63deffc0-98b0-405f-b093-74d10b422b01">
+Copyright - Yehowshua Immanuel
 
 # A High performance, VCD Parser written in Rust
 
-I hope for a GUI that eventually looks like the following...
-
-![](assets/FastWaveMockup.png)
-
 # Current Features
 
  - Robust Error Handling
@@ -52,8 +35,6 @@ slower.
 
 ## Results
 
-LZ4 should really improve memory usage once I add it. Note that GTKWave uses LZ4 on the fly.
-
 | Software | Time(s) | Memory(MB) |
 |----------|---------|------------|
 | FastWave | ~27.30  | 1100+      |
@@ -70,11 +51,9 @@ This repository comes with several smaller VCD files emitted from
 various EDA tools. If you want a larger VCD file, grab one from
 [here](https://drive.google.com/file/d/1pfm2qo2l8fGTHHJ8TLrg1vSGaV_TUbp2/view?usp=sharing).
 
-Here are some examples you can run:
 The first build of the program may take some time.
 
-1. ``cargo run --release --example parse_vcd tests/vcd-files/aldec/SPI_Write.vcd``
-2. ``cargo run --release --example vcd``
+``cargo run --release test-vcd-files/aldec/SPI_Write.vcd``
 
 You can run all the tests with ``cargo test``
 
@@ -83,38 +62,26 @@ You may wish to test the parser on a malformed VCD just to make
 sure that the parser gives useful/sane errors.
 
 Here's a command to test on a malformed VCD:
-``cargo run --release --example parse_vcd tests/vcd-files/VCD_file_with_errors.vcd``
+`cargo run --release test-vcd-files/VCD_file_with_errors.vcd`
 
 
 # TODO
 
 ## Features and Other
- - [ ] add documenting comments
- - [ ] make signal query private until later?
- - [ ] add signal query code to example once interface is finalized
- - [ ] change crate name to vcd_fast_parse
- - [ ] perhaps we should be looking up signal values on the VCD class
- - [ ] perhaps we should be returning signal trees from the VCD class
- - [ ] add lz4 compression support and compare memory perf before and after
-       - [ ] may need to refactor with allow for get_mut for dynamic
-             compression-decompression for multiple signal structs 
-             at once to allow for multi-threading
- - [ ] test against large waveforms from the
-       [verilog-vcd-parser](https://github.com/ben-marshall/verilog-vcd-parser)
-       tool
+ - [ ] add timeline value scanner code
+ - [ ] test against large waveform directly within SpinalHDL
  - [ ] (a bit of work) consolidate error messages in validation phase
- - [ ] once the access patterns of the GUI frontend are well understood,
-       create specific functions and restrict as many types to private
-       as possible
+ - [ ] be explicit with imports, remove exports as possible
+       once FastWave is known to be fairly stable.
+ - [ ] do a read through all the code
+    - make contents of src/types.rs public as necessary.
  - [ ] Print out git commit or release number.
- - [ ] do a read through all the code - look for uneeded code
+ - [ ] Take a look at GTKWave parser to compare efficiency.
  - [ ] Move part of the performance section to another markdown file.
 
 ## Repairs
- - [ ] replace str bracket indices with get(slice)
  - [ ] make a custom date parser for possibly up to 18 different versions(that is, for each possible tool).
  - [ ] Consolidate error messages and add cursors throughout.
- - [ ] Add file and line to the enum errors.
  - [ ] Fix warnings especially usage and restriction warnings once I'm
        able to successfully parse all sample VCDs.
 
@@ -128,4 +95,4 @@ Here's a command to test on a malformed VCD:
  - [ ] Document indexing structure with diagram and possibly include the rational
 
 ## Marketing
- - [ ] Send survey to community 
+ - [ ] Send survey to community 

examples/parse_vcd.rs

@@ -1,33 +0,0 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-use clap::Parser;
-use std::fs::File;
-
-use fastwave_backend::parse_vcd;
-
-#[derive(Parser)]
-struct Cli {
-    /// The path to the file to read
-    path: std::path::PathBuf,
-}
-
-fn main() -> std::io::Result<()> {
-    let args = Cli::parse();
-
-    use std::time::Instant;
-
-    let now = Instant::now();
-    let file = File::open(&args.path)?;
-    parse_vcd(file).unwrap();
-    let elapsed = now.elapsed();
-
-    println!(
-        "Parsed VCD file {} : {:.2?}",
-        &args.path.as_os_str().to_str().unwrap(),
-        elapsed
-    );
-
-    Ok(())
-}

examples/vcd.rs

@@ -1,81 +0,0 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-use std::fs::File;
-
-use fastwave_backend::{parse_vcd, ScopeIdx, SignalIdx, VCD};
-
-fn indented_print(indent: u8, name: &String) {
-    for _ in 0..indent {
-        print!("  |");
-    }
-    print!("---");
-    println!("{name}");
-}
-
-// TODO: refactor into more general visitor pattern that takes a
-// function as an argument.
-fn visit_all_scopes(vcd: &VCD) {
-    fn visit_all_scope_children(root_idx: ScopeIdx, vcd: &VCD, indent: u8) {
-        if vcd.child_scopes_by_idx(root_idx).is_empty() {
-        } else {
-            for child_scope_idx in vcd.child_scopes_by_idx(root_idx) {
-                indented_print(indent, vcd.scope_name_by_idx(child_scope_idx));
-                for signal_idx in vcd.get_children_signal_idxs(child_scope_idx) {
-                    let signal = vcd.signal_from_signal_idx(signal_idx);
-                    let SignalIdx(idx) = signal_idx;
-                    indented_print(indent + 1, &format!("{},{}", signal.name(), idx));
-                }
-                visit_all_scope_children(child_scope_idx, vcd, indent + 1);
-            }
-        }
-    }
-    for root_scope_idx in vcd.root_scopes_by_idx() {
-        indented_print(0, vcd.scope_name_by_idx(root_scope_idx));
-        visit_all_scope_children(root_scope_idx, vcd, 1u8);
-    }
-}
-
-fn main() -> std::io::Result<()> {
-    use std::time::Instant;
-
-    // we start by printing out the entire signal tree of
-    // a parsed VCD
-    let now = Instant::now();
-    let file_path = "tests/vcd-files/icarus/CPU.vcd";
-    let file = File::open(file_path)?;
-    let vcd = parse_vcd(file).unwrap();
-    let elapsed = now.elapsed();
-    println!("Parsed VCD file {} : {:.2?}", file_path, elapsed);
-
-    println!("Printing Scopes");
-    visit_all_scopes(&vcd);
-    println!("Done Printing Scopes");
-    println!();
-
-    // we then parse another VCD, print its signal tree and
-    // query some values on its timeline
-    let now = Instant::now();
-    let file_path = "tests/vcd-files/amaranth/up_counter.vcd";
-    let file = File::open(file_path)?;
-    let vcd = parse_vcd(file).unwrap();
-    let elapsed = now.elapsed();
-    println!("Parsed VCD file {} : {:.2?}", file_path, elapsed);
-
-    println!("Printing Scopes");
-    visit_all_scopes(&vcd);
-    println!("Done Printing Scopes");
-
-    let state_signal = vcd.signal_from_signal_idx(SignalIdx(4));
-    let name = state_signal.name();
-
-    let timestamps = vec![31499_000u32, 31500_000u32, 57760_000u32];
-    for timestamp in timestamps {
-        let time = num::BigUint::from(timestamp);
-        let val = state_signal.query_string_val_on_tmln(&time, &vcd).unwrap();
-        println!("Signal `{name}` has value `{val}` at time `{time}`");
-    }
-
-    Ok(())
-}

src/lib.rs

@@ -1,12 +0,0 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-
-mod vcd;
-pub use vcd::parse::parse_vcd;
-pub use vcd::signal::{Signal, SignalType, SignalValue, SignalErrors};
-pub use vcd::types::{Metadata, Timescale, Version};
-pub use vcd::types::{ScopeIdx, SignalIdx, VCD};
-
-pub use num::BigUint;

src/main.rs

@@ -0,0 +1,31 @@
+use clap::Parser;
+use std::fs::File;
+
+pub mod test;
+
+pub mod vcd;
+use vcd::parse_vcd;
+
+#[derive(Parser)]
+struct Cli {
+    /// The path to the file to read
+    #[clap(parse(from_os_str))]
+    path: std::path::PathBuf,
+}
+
+fn main() -> std::io::Result<()> {
+    let args = Cli::parse();
+
+    use std::time::Instant;
+    let now = Instant::now();
+
+    let file = File::open(&args.path)?;
+    parse_vcd(file).unwrap();
+
+    let elapsed = now.elapsed();
+    println!("Elapsed: {:.2?}", elapsed);
+
+    // std::thread::sleep(std::time::Duration::from_secs(10));
+
+    Ok(())
+}

src/test.rs

@@ -0,0 +1,2 @@
+mod files;
+pub use files::*;

src/test/files.rs

@@ -0,0 +1,71 @@
+// TODO: we should eventually be able to only test on just
+// the files const
+pub const FILES : [&str; 30] = [
+    "./test-vcd-files/aldec/SPI_Write.vcd",
+    "./test-vcd-files/ghdl/alu.vcd",
+    "./test-vcd-files/ghdl/idea.vcd",
+    "./test-vcd-files/ghdl/pcpu.vcd",
+    "./test-vcd-files/gtkwave-analyzer/perm_current.vcd",
+    "./test-vcd-files/icarus/CPU.vcd",
+    "./test-vcd-files/icarus/rv32_soc_TB.vcd",
+    "./test-vcd-files/icarus/test1.vcd",
+    "./test-vcd-files/model-sim/CPU_Design.msim.vcd",
+    "./test-vcd-files/model-sim/clkdiv2n_tb.vcd",
+    "./test-vcd-files/my-hdl/Simple_Memory.vcd",
+    "./test-vcd-files/my-hdl/sigmoid_tb.vcd",
+    "./test-vcd-files/my-hdl/top.vcd",
+    "./test-vcd-files/ncsim/ffdiv_32bit_tb.vcd",
+    "./test-vcd-files/quartus/mipsHardware.vcd",
+    "./test-vcd-files/quartus/wave_registradores.vcd",
+    "./test-vcd-files/questa-sim/dump.vcd",
+    "./test-vcd-files/questa-sim/test.vcd",
+    "./test-vcd-files/riviera-pro/dump.vcd",
+    "./test-vcd-files/systemc/waveform.vcd",
+    "./test-vcd-files/treadle/GCD.vcd",
+    "./test-vcd-files/vcs/Apb_slave_uvm_new.vcd",
+    "./test-vcd-files/vcs/datapath_log.vcd",
+    "./test-vcd-files/vcs/processor.vcd",
+    "./test-vcd-files/verilator/swerv1.vcd",
+    "./test-vcd-files/verilator/vlt_dump.vcd",
+    "./test-vcd-files/vivado/iladata.vcd",
+    "./test-vcd-files/xilinx_isim/test.vcd",
+    "./test-vcd-files/xilinx_isim/test1.vcd",
+    // TODO : add signal ignore list to handle bitwidth mismatches
+    "./test-vcd-files/xilinx_isim/test2x2_regex22_string1.vcd"
+];
+
+pub const GOOD_DATE_FILES : [&str; 24] = [
+    "./test-vcd-files/aldec/SPI_Write.vcd",
+    "./test-vcd-files/ghdl/alu.vcd",
+    "./test-vcd-files/ghdl/idea.vcd",
+    "./test-vcd-files/ghdl/pcpu.vcd",
+    "./test-vcd-files/gtkwave-analyzer/perm_current.vcd",
+    "./test-vcd-files/icarus/CPU.vcd",
+    "./test-vcd-files/icarus/rv32_soc_TB.vcd",
+    "./test-vcd-files/icarus/test1.vcd",
+    "./test-vcd-files/model-sim/CPU_Design.msim.vcd",
+    "./test-vcd-files/model-sim/clkdiv2n_tb.vcd",
+    "./test-vcd-files/my-hdl/Simple_Memory.vcd",
+    "./test-vcd-files/my-hdl/sigmoid_tb.vcd",
+    "./test-vcd-files/my-hdl/top.vcd",
+    "./test-vcd-files/questa-sim/dump.vcd",
+    "./test-vcd-files/questa-sim/test.vcd",
+    "./test-vcd-files/riviera-pro/dump.vcd",
+    "./test-vcd-files/vcs/Apb_slave_uvm_new.vcd",
+    "./test-vcd-files/vcs/datapath_log.vcd",
+    "./test-vcd-files/vcs/processor.vcd",
+    "./test-vcd-files/verilator/swerv1.vcd",
+    "./test-vcd-files/verilator/vlt_dump.vcd",
+    "./test-vcd-files/xilinx_isim/test.vcd",
+    "./test-vcd-files/xilinx_isim/test1.vcd",
+    "./test-vcd-files/xilinx_isim/test2x2_regex22_string1.vcd"
+];
+
+pub const BAD_DATE_FILES : [&str; 6] = [
+    "./test-vcd-files/ncsim/ffdiv_32bit_tb.vcd",
+    "./test-vcd-files/quartus/mipsHardware.vcd",
+    "./test-vcd-files/quartus/wave_registradores.vcd",
+    "./test-vcd-files/systemc/waveform.vcd",
+    "./test-vcd-files/treadle/GCD.vcd",
+    "./test-vcd-files/vivado/iladata.vcd",
+];

src/vcd.rs

@@ -1,10 +1,14 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-
-pub(crate) mod parse;
 mod reader;
-pub(crate) mod signal;
-pub(crate) mod types;
+use reader::*;
+
+mod types;
+use types::*;
+
+mod parse;
+pub use parse::*;
+
+mod signal;
+use signal::*;
+
 mod utilities;
+use utilities::*;

src/vcd/parse.rs

@@ -1,35 +1,100 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
+use num::BigUint;
+use std::collections::HashMap;
+use std::fs::File;
+
+use super::*;
 
 mod combinator_atoms;
-mod events;
-mod metadata;
-mod scopes;
+use combinator_atoms::*;
+
 mod types;
+use types::*;
 
-pub fn parse_vcd(file: impl std::io::Read) -> Result<super::types::VCD, String> {
-    let mut word_gen = super::reader::WordReader::new(file);
+mod metadata;
+use metadata::*;
 
-    let header = metadata::parse_metadata(&mut word_gen)?;
+mod scopes;
+use scopes::*;
+
+mod events;
+use events::*;
+
+pub fn parse_vcd(file: File) -> Result<VCD, String> {
+    let mut word_gen = WordReader::new(file);
+
+    let header = parse_metadata(&mut word_gen)?;
 
     // later, we'll need to map parsed ascii symbols to their
     // respective signal indexes
     let mut signal_map = std::collections::HashMap::new();
 
     // after we parse metadata, we form the VCD object
-    let mut vcd = super::types::VCD {
+    let mut vcd = VCD {
         metadata: header,
         tmstmps_encoded_as_u8s: vec![],
         all_signals: vec![],
         all_scopes: vec![],
         root_scopes: vec![],
-        largest_timestamp: None,
     };
 
-    scopes::parse_scopes(&mut word_gen, &mut vcd, &mut signal_map)?;
-    events::parse_events(&mut word_gen, &mut vcd, &mut signal_map)?;
+    parse_scopes(&mut word_gen, &mut vcd, &mut signal_map)?;
+    parse_events(&mut word_gen, &mut vcd, &mut signal_map)?;
+    let signal = vcd.try_dereference_alias(signal_map.get("Q").unwrap())?;
+    let name = match signal {
+        Signal::Data { name, .. } => name,
+        _ => "ERROR",
+    };
+    let val = signal
+        .query_num_val_on_tmln(
+            BigUint::from(4687u32),
+            &vcd.tmstmps_encoded_as_u8s,
+            &vcd.all_signals,
+        )
+        .unwrap();
+    dbg!(format!("{val:#X}"));
+    dbg!(name);
 
     Ok(vcd)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::test;
+    use std::fs::File;
+    #[test]
+    fn headers() {
+        // TODO: eventually, once all dates pass, merge the following
+        // two loops
+        // testing dates
+        for file in test::GOOD_DATE_FILES {
+            let metadata = parse_metadata(&mut WordReader::new(File::open(file).unwrap()));
+            assert!(metadata.is_ok());
+            assert!(metadata.unwrap().date.is_some());
+        }
+
+        for file in test::FILES {
+            let metadata = parse_metadata(&mut WordReader::new(File::open(file).unwrap()));
+            assert!(metadata.is_ok());
+
+            let (scalar, _timescale) = metadata.unwrap().timescale;
+            assert!(scalar.is_some());
+        }
+    }
+
+    #[test]
+    fn scopes() {
+        // see if we can parse all signal trees successfully
+        for file_name in test::FILES {
+            let file = File::open(file_name).unwrap();
+            let vcd = parse_vcd(file);
+
+            if !vcd.is_ok() {
+                dbg!(file_name);
+                vcd.unwrap();
+            }
+
+            // assert!(vcd.is_ok());
+        }
+    }
+}

src/vcd/parse/combinator_atoms.rs

@@ -1,18 +1,16 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-use super::super::reader::{next_word, WordReader};
+use super::reader::{next_word, WordReader};
 use super::types::ParseResult;
 
 pub(super) fn digit(chr: u8) -> bool {
-    let zero = b'0';
-    let nine = b'9';
+    let zero = b'0' as u8;
+    let nine = b'9' as u8;
 
-    (chr >= zero) && (nine >= chr)
+    let between_zero_and_nine = (chr >= zero) && (nine >= chr);
+
+    return between_zero_and_nine;
 }
 
-pub(super) fn take_until(word: &str, pattern: u8) -> ParseResult<'_> {
+pub(super) fn take_until<'a>(word: &'a str, pattern: u8) -> ParseResult<'a> {
     let mut new_start = 0;
 
     for chr in word.as_bytes() {
@@ -23,13 +21,13 @@ pub(super) fn take_until(word: &str, pattern: u8) -> ParseResult<'_> {
         }
     }
 
-    ParseResult {
+    return ParseResult {
         matched: &word[0..new_start],
         residual: &word[new_start..],
-    }
+    };
 }
 
-pub(super) fn take_while(word: &str, cond: fn(u8) -> bool) -> ParseResult<'_> {
+pub(super) fn take_while<'a>(word: &'a str, cond: fn(u8) -> bool) -> ParseResult<'a> {
     let mut new_start = 0;
 
     for chr in word.as_bytes() {
@@ -40,10 +38,10 @@ pub(super) fn take_while(word: &str, cond: fn(u8) -> bool) -> ParseResult<'_> {
         }
     }
 
-    ParseResult {
+    return ParseResult {
         matched: &word[0..new_start],
         residual: &word[new_start..],
-    }
+    };
 }
 
 pub(super) fn tag<'a>(word: &'a str, pattern: &'a str) -> ParseResult<'a> {
@@ -61,23 +59,20 @@ pub(super) fn tag<'a>(word: &'a str, pattern: &'a str) -> ParseResult<'a> {
         new_start += 1;
     }
 
-    ParseResult {
+    return ParseResult {
         matched: &word[0..new_start],
         residual: &word[new_start..],
-    }
+    };
 }
 
-pub(super) fn ident<R: std::io::Read>(
-    word_reader: &mut WordReader<R>,
-    keyword: &str,
-) -> Result<(), String> {
+pub(super) fn ident(word_reader: &mut WordReader, keyword: &str) -> Result<(), String> {
     // let keyword = "module";
     let (word, cursor) = next_word!(word_reader)?;
 
     if word == keyword {
-        Ok(())
+        return Ok(());
     } else {
         let err = format!("found keyword `{word}` but expected `{keyword}` on {cursor:?}");
-        Err(err)
+        return Err(err);
     }
 }

src/vcd/parse/events.rs

@@ -1,23 +1,15 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
+use num::Zero;
 
-use num::BigUint;
-use std::collections::HashMap;
+use super::*;
 
-use super::super::reader::{next_word, Cursor, Line, Word, WordReader};
-use super::super::signal::{LsbIdxOfTmstmpValOnTmln, SignalEnum};
-use super::super::types::{SignalIdx, VCD};
-use super::super::utilities::{binary_str_to_vec_u8, BinaryParserErrTypes};
-
-pub(super) fn parse_events<R: std::io::Read>(
-    word_reader: &mut WordReader<R>,
-    vcd: &mut VCD,
+pub(super) fn parse_events<'a>(
+    word_reader: &mut WordReader,
+    vcd: &'a mut VCD,
     signal_map: &mut HashMap<String, SignalIdx>,
 ) -> Result<(), String> {
     let mut curr_tmstmp_lsb_idx = 0u32;
     let mut curr_tmstmp_len_u8 = 0u8;
+    let mut curr_time = BigUint::zero();
     loop {
         let next_word = word_reader.next_word();
 
@@ -39,14 +31,15 @@ pub(super) fn parse_events<R: std::io::Read>(
             "#" => {
                 let value = &word[1..];
                 let (f, l) = (file!(), line!());
-                let value_biguint = BigUint::parse_bytes(value.as_bytes(), 10)
+                let value = BigUint::parse_bytes(value.as_bytes(), 10)
                     .ok_or(())
                     .map_err(|_| {
                         format!(
                             "Error near {f}:{l}. Failed to parse {value} as BigInt at {cursor:?}"
                         )
                     })?;
-                let mut value = value_biguint.to_bytes_le();
+                curr_time = value.clone();
+                let mut value = value.to_bytes_le();
                 // TODO : u32 helps with less memory, but should ideally likely be
                 // configurable.
                 curr_tmstmp_len_u8 = u8::try_from(value.len()).map_err(|_| {
@@ -65,16 +58,15 @@ pub(super) fn parse_events<R: std::io::Read>(
                         )
                     })?;
                 vcd.tmstmps_encoded_as_u8s.append(&mut value);
-                vcd.largest_timestamp = Some(value_biguint);
             }
 
             // handle the case of an n bit signal whose value must be parsed
             "b" => {
                 let binary_value = &word[1..];
-                let observed_num_bits = u32::try_from(binary_value.len()).map_err(|_| {
+                let observed_num_bits = u16::try_from(binary_value.len()).map_err(|_| {
                     format!(
                         "Error near {}:{}, {cursor:?}. \
-                        Found signal with more than 2^32 - 1 bits.",
+                        Found signal with more than 2^16 - 1 bits.",
                         file!(),
                         line!()
                     )
@@ -85,9 +77,9 @@ pub(super) fn parse_events<R: std::io::Read>(
 
                 let mut store_as_string = false;
 
-                // If we encounter other values than 0 or 1, we can recover from
+                // If we encounter x or z in a value, we can recover from
                 // the error and store the value as a string.
-                // Or else, we propagate up other errors.
+                // Or else, we we propagate up other errors.
                 match binary_str_to_vec_u8(binary_value) {
                     Ok(result) => {
                         value_u8 = result;
@@ -95,15 +87,10 @@ pub(super) fn parse_events<R: std::io::Read>(
                     Err(
                         BinaryParserErrTypes::XValue
                         | BinaryParserErrTypes::ZValue
-                        | BinaryParserErrTypes::UValue
-                        | BinaryParserErrTypes::WValue
-                        | BinaryParserErrTypes::HValue
-                        | BinaryParserErrTypes::DashValue
-                        | BinaryParserErrTypes::LValue,
+                        | BinaryParserErrTypes::UValue,
                     ) => {
                         store_as_string = true;
-                        // Turn to lower case for consistency
-                        value_string = binary_value.to_ascii_lowercase();
+                        value_string = binary_value.to_string();
                     }
                     Err(e) => {
                         let (f, l) = (file!(), line!());
@@ -125,12 +112,12 @@ pub(super) fn parse_events<R: std::io::Read>(
                     )
                 })?;
 
-                let signal = vcd.dealiasing_signal_idx_to_signal_lookup_mut(signal_idx)?;
+                let signal = vcd.try_dereference_alias_mut(signal_idx)?;
 
                 match signal {
-                    SignalEnum::Data {
+                    Signal::Data {
                         name,
-                        signal_type,
+                        sig_type,
                         ref mut signal_error,
                         num_bits,
                         num_bytes,
@@ -139,7 +126,6 @@ pub(super) fn parse_events<R: std::io::Read>(
                         lsb_indxs_of_num_tmstmp_vals_on_tmln,
                         byte_len_of_num_tmstmp_vals_on_tmln,
                         lsb_indxs_of_string_tmstmp_vals_on_tmln,
-                        byte_len_of_string_tmstmp_vals_on_tmln,
                         ..
                     } => {
                         // we've already identified in a prior loop iteration that the signal has
@@ -158,7 +144,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                                     let (f, l) = (file!(), line!());
                                     let msg = format!("\
                                         Error near {f}:{l}. The bitwidth for signal {name} \
-                                        of signal_type {signal_type:?} is expected to be `{num_bits}` not \
+                                        of sig_type {sig_type:?} is expected to be `{num_bits}` not \
                                         `{observed_num_bits}`. \
                                         This error occurred while parsing the vcd file at \
                                         {cursor:?}");
@@ -171,7 +157,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                                 let msg = format!(
                                     "\
                                     Error near {f}:{l}. The bitwidth for signal {name} \
-                                    must be specified for a signal of type {signal_type:?}. \
+                                    must be specified for a signal of type {sig_type:?}. \
                                     This error occurred while parsing the vcd file at \
                                     {cursor:?}"
                                 );
@@ -182,7 +168,6 @@ pub(super) fn parse_events<R: std::io::Read>(
                         if store_as_string {
                             lsb_indxs_of_string_tmstmp_vals_on_tmln
                                 .push(LsbIdxOfTmstmpValOnTmln(curr_tmstmp_lsb_idx));
-                            byte_len_of_string_tmstmp_vals_on_tmln.push(curr_tmstmp_len_u8);
                             string_vals.push(value_string);
                             Ok(())
                         } else {
@@ -200,11 +185,11 @@ pub(super) fn parse_events<R: std::io::Read>(
                                 format!("Error near {}:{}. num_bytes empty.", file!(), line!())
                             })?;
                             let mut curr_num_bytes =
-                                u16::try_from(value_u8.len()).map_err(|_| {
+                                u8::try_from(value_u8.len()).map_err(|_| {
                                     format!(
                                         "Error near {}:{}. \
                                      Found signal {name} with with value change of greater \
-                                     than 2^32 - 1 bits on {cursor:?}.",
+                                     than 2^16 - 1 bits on {cursor:?}.",
                                         file!(),
                                         line!()
                                     )
@@ -218,7 +203,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                             Ok(())
                         }
                     }
-                    SignalEnum::Alias { .. } => {
+                    Signal::Alias { .. } => {
                         let (f, l) = (file!(), line!());
                         let msg = format!(
                             "Error near {f}:{l}, a signal alias should not point to a signal alias.\n\
@@ -240,12 +225,12 @@ pub(super) fn parse_events<R: std::io::Read>(
                     )
                 })?;
 
-                let signal = vcd.dealiasing_signal_idx_to_signal_lookup_mut(signal_idx)?;
+                let signal = vcd.try_dereference_alias_mut(signal_idx)?;
 
                 match signal {
-                    SignalEnum::Data {
+                    Signal::Data {
                         name,
-                        signal_type,
+                        sig_type,
                         ref mut signal_error,
                         num_bits,
                         num_bytes,
@@ -268,7 +253,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                                     let msg = format!(
                                         "\
                                         Error near {f}:{l}. The bitwidth for signal {name} \
-                                        of signal_type {signal_type:?} is expected to be `1` not \
+                                        of sig_type {sig_type:?} is expected to be `1` not \
                                         `{num_bits}`. \
                                         This error occurred while parsing the vcd file at \
                                         {cursor:?}"
@@ -282,7 +267,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                                 let msg = format!(
                                     "\
                                     Error near {f}:{l}. The bitwidth for signal {name} \
-                                    must be specified for a signal of type {signal_type:?}. \
+                                    must be specified for a signal of type {sig_type:?}. \
                                     This error occurred while parsing the vcd file at \
                                     {cursor:?}"
                                 );
@@ -310,7 +295,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                         }
                         Ok(())
                     }
-                    SignalEnum::Alias { .. } => {
+                    Signal::Alias { .. } => {
                         let (f, l) = (file!(), line!());
                         let msg = format!(
                             "Error near {f}:{l}, a signal alias should not point to a signal alias.\n\
@@ -331,12 +316,12 @@ pub(super) fn parse_events<R: std::io::Read>(
                     )
                 })?;
 
-                let signal = vcd.dealiasing_signal_idx_to_signal_lookup_mut(signal_idx)?;
+                let signal = vcd.try_dereference_alias_mut(signal_idx)?;
 
                 match signal {
-                    SignalEnum::Data {
+                    Signal::Data {
                         name,
-                        signal_type,
+                        sig_type,
                         ref mut signal_error,
                         num_bits,
                         num_bytes,
@@ -359,7 +344,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                                     let msg = format!(
                                         "\
                                         Error near {f}:{l}. The bitwidth for signal {name} \
-                                        of signal_type {signal_type:?} is expected to be `1` not \
+                                        of sig_type {sig_type:?} is expected to be `1` not \
                                         `{num_bits}`. \
                                         This error occurred while parsing the vcd file at \
                                         {cursor:?}"
@@ -373,7 +358,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                                 let msg = format!(
                                     "\
                                     Error near {f}:{l}. The bitwidth for signal {name} \
-                                    must be specified for a signal of type {signal_type:?}. \
+                                    must be specified for a signal of type {sig_type:?}. \
                                     This error occurred while parsing the vcd file at \
                                     {cursor:?}"
                                 );
@@ -401,7 +386,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                         }
                         Ok(())
                     }
-                    SignalEnum::Alias { .. } => {
+                    Signal::Alias { .. } => {
                         let (f, l) = (file!(), line!());
                         let msg = format!(
                             "Error near {f}:{l}, a signal alias should not point to a signal alias.\n\
@@ -411,10 +396,9 @@ pub(super) fn parse_events<R: std::io::Read>(
                 }?;
             }
 
-            // other one bit cases
-            "x" | "X" | "z" | "Z" | "u" | "U" | "h" | "H" | "l" | "L" | "w" | "W" | "-" => {
-                // Select value and turn to lowercase for consistency
-                let val = word[0..1].to_ascii_lowercase();
+            // // other one bit cases
+            "x" | "X" | "z" | "Z" | "u" | "U" => {
+                let val = word.to_string();
                 // lokup signal idx
                 let hash = &word[1..];
                 let signal_idx = signal_map.get(hash).ok_or(()).map_err(|_| {
@@ -425,15 +409,16 @@ pub(super) fn parse_events<R: std::io::Read>(
                     )
                 })?;
 
-                let signal = vcd.dealiasing_signal_idx_to_signal_lookup_mut(signal_idx)?;
+                let signal = vcd.try_dereference_alias_mut(signal_idx)?;
 
                 match signal {
-                    SignalEnum::Data {
+                    Signal::Data {
                         name,
-                        signal_type,
+                        sig_type,
                         ref mut signal_error,
                         num_bits,
                         string_vals,
+                        byte_len_of_num_tmstmp_vals_on_tmln,
                         byte_len_of_string_tmstmp_vals_on_tmln,
                         lsb_indxs_of_string_tmstmp_vals_on_tmln,
                         ..
@@ -452,7 +437,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                                     let msg = format!(
                                         "\
                                         Error near {f}:{l}. The bitwidth for signal {name} \
-                                        of signal_type {signal_type:?} is expected to be `1` not \
+                                        of sig_type {sig_type:?} is expected to be `1` not \
                                         `{num_bits}`. \
                                         This error occurred while parsing the vcd file at \
                                         {cursor:?}"
@@ -466,7 +451,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                                 let msg = format!(
                                     "\
                                     Error near {f}:{l}. The bitwidth for signal {name} \
-                                    must be specified for a signal of type {signal_type:?}. \
+                                    must be specified for a signal of type {sig_type:?}. \
                                     This error occurred while parsing the vcd file at \
                                     {cursor:?}"
                                 );
@@ -483,53 +468,7 @@ pub(super) fn parse_events<R: std::io::Read>(
                         string_vals.push(val);
                         Ok(())
                     }
-                    SignalEnum::Alias { .. } => {
-                        let (f, l) = (file!(), line!());
-                        let msg = format!(
-                            "Error near {f}:{l}, a signal alias should not point to a signal alias.\n\
-                             This error occurred while parsing vcd file at {cursor:?}");
-                        Err(msg)
-                    }
-                }?;
-            }
-            // Store real values as a string as well and let the user parse it to an f64
-            "s" | " S" | "r" | "R" => {
-                let val = word[1..].to_string();
-                let (hash, cursor) = next_word!(word_reader)?;
-                // lokup signal idx
-                let signal_idx = signal_map.get(hash).ok_or(()).map_err(|_| {
-                    format!(
-                        "Error near {}:{}. Failed to lookup signal {hash} at {cursor:?}",
-                        file!(),
-                        line!()
-                    )
-                })?;
-
-                let signal = vcd.dealiasing_signal_idx_to_signal_lookup_mut(signal_idx)?;
-
-                match signal {
-                    SignalEnum::Data {
-                        ref mut signal_error,
-                        string_vals,
-                        byte_len_of_string_tmstmp_vals_on_tmln,
-                        lsb_indxs_of_string_tmstmp_vals_on_tmln,
-                        ..
-                    } => {
-                        // if this is a bad signal, go ahead and skip it
-                        if signal_error.is_some() {
-                            continue;
-                        }
-
-                        // record timestamp at which this event occurs
-                        lsb_indxs_of_string_tmstmp_vals_on_tmln
-                            .push(LsbIdxOfTmstmpValOnTmln(curr_tmstmp_lsb_idx));
-                        byte_len_of_string_tmstmp_vals_on_tmln.push(curr_tmstmp_len_u8);
-
-                        // record string value
-                        string_vals.push(val);
-                        Ok(())
-                    }
-                    SignalEnum::Alias { .. } => {
+                    Signal::Alias { .. } => {
                         let (f, l) = (file!(), line!());
                         let msg = format!(
                             "Error near {f}:{l}, a signal alias should not point to a signal alias.\n\

src/vcd/parse/metadata.rs

@@ -1,15 +1,7 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-use chrono::prelude::{DateTime, Utc};
+use chrono::prelude::*;
 use itertools::Itertools;
 
-use super::super::reader::{next_word, Cursor, WordReader};
-use super::super::types::{Metadata, Timescale, Version};
-
-use super::combinator_atoms::{digit, tag, take_until, take_while};
-use super::types::ParseResult;
+use super::*;
 
 pub(super) fn parse_date(
     word_and_ctx1: (&str, &Cursor),
@@ -133,9 +125,9 @@ pub(super) fn parse_date(
     // unfortunately, the minutes, seconds, and hour could occur in an
     // unexpected order
     let full_date = format!("{day} {month} {date} {hh}:{mm}:{ss} {year}");
-    let full_date = DateTime::parse_from_str(full_date.as_str(), "%a %b %e %T %Y");
+    let full_date = Utc.datetime_from_str(full_date.as_str(), "%a %b %e %T %Y");
     if full_date.is_ok() {
-        return Ok(full_date.unwrap().into());
+        return Ok(full_date.unwrap());
     }
 
     Err(format!(
@@ -145,9 +137,7 @@ pub(super) fn parse_date(
     ))
 }
 
-pub(super) fn parse_version<R: std::io::Read>(
-    word_reader: &mut WordReader<R>,
-) -> Result<Version, String> {
+pub(super) fn parse_version(word_reader: &mut WordReader) -> Result<Version, String> {
     let mut version = String::new();
 
     loop {
@@ -159,13 +149,13 @@ pub(super) fn parse_version<R: std::io::Read>(
             return Ok(Version(version));
         } else {
             version.push_str(word);
-            version.push(' ');
+            version.push_str(" ");
         }
     }
 }
 
-pub(super) fn parse_timescale<R: std::io::Read>(
-    word_reader: &mut WordReader<R>,
+pub(super) fn parse_timescale(
+    word_reader: &mut WordReader,
 ) -> Result<(Option<u32>, Timescale), String> {
     // we might see `1ps $end` or `1 ps $end`
     // first get timescale
@@ -179,7 +169,7 @@ pub(super) fn parse_timescale<R: std::io::Read>(
         .map_err(|e| format!("Error near {}:{}. {e}", file!(), line!()))?;
 
     let timescale = {
-        if residual.is_empty() {
+        if residual == "" {
             let (word, _) = next_word!(word_reader)?;
             let unit = match word {
                 "fs" => Ok(Timescale::Fs),
@@ -219,12 +209,10 @@ pub(super) fn parse_timescale<R: std::io::Read>(
     let (word, _) = next_word!(word_reader)?;
     tag(word, "$end").assert_match()?;
 
-    Ok(timescale)
+    return Ok(timescale);
 }
 
-pub(super) fn parse_metadata<R: std::io::Read>(
-    word_reader: &mut WordReader<R>,
-) -> Result<Metadata, String> {
+pub(super) fn parse_metadata(word_reader: &mut WordReader) -> Result<Metadata, String> {
     let mut metadata = Metadata {
         date: None,
         version: None,
@@ -331,5 +319,5 @@ pub(super) fn parse_metadata<R: std::io::Read>(
             _ => {}
         }
     }
-    Ok(metadata)
+    return Ok(metadata);
 }

src/vcd/parse/scopes.rs

@@ -1,71 +1,36 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
+//! part of the vcd parser that handles parsing the signal tree and
+//! building the resulting signal tree
+use super::*;
 
-/// part of the vcd parser that handles parsing the signal tree and
-/// building the resulting signal tree
-use std::collections::HashMap;
-
-use super::super::reader::{curr_word, next_word, WordReader};
-use super::super::signal::{SignalEnum, SignalType};
-use super::super::types::{Scope, ScopeIdx, SignalIdx, VCD};
-
-use super::combinator_atoms::{ident, tag};
-use super::types::ParseResult;
-
-pub(super) fn parse_var<R: std::io::Read>(
-    word_reader: &mut WordReader<R>,
+pub(super) fn parse_var<'a>(
+    word_reader: &mut WordReader,
     parent_scope_idx: ScopeIdx,
-    vcd: &mut VCD,
+    vcd: &'a mut VCD,
     signal_map: &mut HashMap<String, SignalIdx>,
-    path: &Vec<String>,
 ) -> Result<(), String> {
     let (word, cursor) = next_word!(word_reader)?;
     let expected_types = [
-        "event",
         "integer",
         "parameter",
         "real",
-        "realtime",
         "reg",
         "string",
-        "supply0",
-        "supply1",
-        "time",
-        "tri",
-        "triand",
-        "trior",
-        "trireg",
-        "tri0",
-        "tri1",
-        "wand",
         "wire",
-        "wor",
+        "tri1",
+        "time",
     ];
 
     // $var parameter 3 a IDLE $end
     //      ^^^^^^^^^ - var_type
     let var_type = match word {
-        "event" => Ok(SignalType::Event),
-        "integer" => Ok(SignalType::Integer),
-        "parameter" => Ok(SignalType::Parameter),
-        "real" => Ok(SignalType::Real),
-        "realtime" => Ok(SignalType::RealTime),
-        "reg" => Ok(SignalType::Reg),
-        "string" => Ok(SignalType::Str),
-        "supply0" => Ok(SignalType::Supply0),
-        "supply1" => Ok(SignalType::Supply1),
-        "tri" => Ok(SignalType::Tri),
-        "triand" => Ok(SignalType::TriAnd),
-        "trior" => Ok(SignalType::TriOr),
-        "trireg" => Ok(SignalType::TriReg),
-        "tri0" => Ok(SignalType::Tri0),
-        "tri1" => Ok(SignalType::Tri1),
-        "time" => Ok(SignalType::Time),
-        "wand" => Ok(SignalType::WAnd),
-        "wire" => Ok(SignalType::Wire),
-        "wor" => Ok(SignalType::WOr),
+        "integer" => Ok(SigType::Integer),
+        "parameter" => Ok(SigType::Parameter),
+        "real" => Ok(SigType::Real),
+        "reg" => Ok(SigType::Reg),
+        "string" => Ok(SigType::Str),
+        "wire" => Ok(SigType::Wire),
+        "tri1" => Ok(SigType::Tri1),
+        "time" => Ok(SigType::Time),
         _ => {
             let err = format!(
                 "Error near {}:{} \
@@ -85,36 +50,25 @@ pub(super) fn parse_var<R: std::io::Read>(
     // $var parameter 3 a IDLE $end
     //                ^ - num_bits
     let num_bits = match var_type {
-        SignalType::Event
-        | SignalType::Integer
-        | SignalType::Parameter
-        | SignalType::Reg
-        | SignalType::Supply0
-        | SignalType::Supply1
-        | SignalType::Tri
-        | SignalType::TriAnd
-        | SignalType::TriOr
-        | SignalType::TriReg
-        | SignalType::Tri0
-        | SignalType::Tri1
-        | SignalType::Time
-        | SignalType::WAnd
-        | SignalType::Wire
-        | SignalType::WOr => {
-            let num_bits = word
-                .parse::<usize>()
-                .unwrap_or_else(|_| panic!("{}", parse_err));
-            let num_bits = u32::try_from(num_bits).map_err(|_| {
+        SigType::Integer
+        | SigType::Parameter
+        | SigType::Real
+        | SigType::Reg
+        | SigType::Wire
+        | SigType::Tri1
+        | SigType::Time => {
+            let num_bits = word.parse::<usize>().expect(parse_err.as_str());
+            let num_bits = u16::try_from(num_bits).map_err(|_| {
                 format!(
                     "Error near {}:{} while parsing vcd file at {cursor:?}. \
-                     This signal has {num_bits} > 2^32 - 1 bits.",
+                     This signal has {num_bits} > 2^16 - 1 bits.",
                     file!(),
                     line!()
                 )
             })?;
             Some(num_bits)
         }
-        // for strings, reals, and realtimes we don't really care what the number of bits is
+        // for strings, we don't really care what the number of bits is
         _ => None,
     };
 
@@ -126,19 +80,17 @@ pub(super) fn parse_var<R: std::io::Read>(
     // $var parameter 3 a IDLE $end
     //                    ^^^^ - full_signal_name(can extend until $end)
     let mut full_signal_name = Vec::<String>::new();
-    let mut size = None;
     loop {
         let (word, _) = next_word!(word_reader)?;
         match word {
             "$end" => break,
-            other if other.starts_with('[') => size = Some(other.to_string()),
             _ => full_signal_name.push(word.to_string()),
         }
     }
     let full_signal_name = full_signal_name.join(" ");
 
     let num_bytes = if num_bits.is_some() {
-        let bytes_required = SignalEnum::bytes_required(num_bits.unwrap(), &full_signal_name)?;
+        let bytes_required = Signal::bytes_required(num_bits.unwrap(), &full_signal_name)?;
         Some(bytes_required)
     } else {
         None
@@ -150,13 +102,8 @@ pub(super) fn parse_var<R: std::io::Read>(
     let (signal, signal_idx) = match signal_map.get(&signal_alias) {
         Some(ref_signal_idx) => {
             let signal_idx = SignalIdx(vcd.all_signals.len());
-            let signal = SignalEnum::Alias {
-                name: full_signal_name.clone(),
-                path: path
-                    .iter()
-                    .cloned()
-                    .chain([full_signal_name])
-                    .collect::<Vec<String>>(),
+            let signal = Signal::Alias {
+                name: full_signal_name,
                 signal_alias: *ref_signal_idx,
             };
             (signal, signal_idx)
@@ -164,18 +111,12 @@ pub(super) fn parse_var<R: std::io::Read>(
         None => {
             let signal_idx = SignalIdx(vcd.all_signals.len());
             signal_map.insert(signal_alias.to_string(), signal_idx);
-            let signal = SignalEnum::Data {
-                name: full_signal_name.clone(),
-                path: path
-                    .iter()
-                    .cloned()
-                    .chain([full_signal_name])
-                    .collect::<Vec<String>>(),
-                signal_type: var_type,
-                index: size,
+            let signal = Signal::Data {
+                name: full_signal_name,
+                sig_type: var_type,
                 signal_error: None,
-                num_bits,
-                num_bytes,
+                num_bits: num_bits,
+                num_bytes: num_bytes,
                 self_idx: signal_idx,
                 nums_encoded_as_fixed_width_le_u8: vec![],
                 string_vals: vec![],
@@ -183,6 +124,7 @@ pub(super) fn parse_var<R: std::io::Read>(
                 byte_len_of_num_tmstmp_vals_on_tmln: vec![],
                 byte_len_of_string_tmstmp_vals_on_tmln: vec![],
                 lsb_indxs_of_string_tmstmp_vals_on_tmln: vec![],
+                scope_parent: parent_scope_idx,
             };
             (signal, signal_idx)
         }
@@ -198,9 +140,9 @@ pub(super) fn parse_var<R: std::io::Read>(
 
 /// Sometimes, variables can be listed outside of scopes.
 /// We call these orphaned vars.
-fn parse_orphaned_vars<R: std::io::Read>(
-    word_reader: &mut WordReader<R>,
-    vcd: &mut VCD,
+fn parse_orphaned_vars<'a>(
+    word_reader: &mut WordReader,
+    vcd: &'a mut VCD,
     signal_map: &mut HashMap<String, SignalIdx>,
 ) -> Result<(), String> {
     // create scope for unscoped signals if such a scope does not
@@ -226,6 +168,7 @@ fn parse_orphaned_vars<R: std::io::Read>(
     if !scope_already_exists {
         vcd.all_scopes.push(Scope {
             name: scope_name.to_string(),
+            parent_idx: None,
             self_idx: scope_idx,
             child_signals: vec![],
             child_scopes: vec![],
@@ -235,14 +178,14 @@ fn parse_orphaned_vars<R: std::io::Read>(
 
     // we can go ahead and parse the current var as we've already encountered
     // "$var" before now.
-    parse_var(word_reader, scope_idx, vcd, signal_map, &vec![])?;
+    parse_var(word_reader, scope_idx, vcd, signal_map)?;
 
     loop {
         let (word, cursor) = next_word!(word_reader)?;
 
         match word {
             "$var" => {
-                parse_var(word_reader, scope_idx, vcd, signal_map, &vec![])?;
+                parse_var(word_reader, scope_idx, vcd, signal_map)?;
             }
             "$scope" => break,
             _ => {
@@ -261,18 +204,17 @@ fn parse_orphaned_vars<R: std::io::Read>(
     Ok(())
 }
 
-fn parse_scopes_inner<R: std::io::Read>(
-    word_reader: &mut WordReader<R>,
+fn parse_scopes_inner<'a>(
+    word_reader: &mut WordReader,
     parent_scope_idx: Option<ScopeIdx>,
-    vcd: &mut VCD,
+    vcd: &'a mut VCD,
     signal_map: &mut HashMap<String, SignalIdx>,
-    path: &Vec<String>,
 ) -> Result<(), String> {
     // $scope module reg_mag_i $end
     //        ^^^^^^ - module keyword
     let (keyword, cursor) = next_word!(word_reader)?;
 
-    let expected = ["module", "begin", "task", "function", "fork"];
+    let expected = ["module", "begin", "task", "function"];
     if expected.contains(&keyword) {
         Ok(())
     } else {
@@ -289,154 +231,79 @@ fn parse_scopes_inner<R: std::io::Read>(
     // $scope module reg_mag_i $end
     //               ^^^^^^^^^ - scope name
     let (scope_name, _) = next_word!(word_reader)?;
-    // In some cases there are VCD files which have scopes without names.
-    // since these occur in the wild, we'll tolerate them even if it is unclear
-    // if it is supported or not by the spec.
-    if scope_name != "$end" {
-        let mut path = path.clone();
-        path.push(scope_name.to_string());
 
-        let curr_scope_idx = ScopeIdx(vcd.all_scopes.len());
+    let curr_scope_idx = ScopeIdx(vcd.all_scopes.len());
 
-        // register this scope as a child of the current parent scope
-        // if there is a parent scope, or else we register this scope as
-        // root scope
-        match parent_scope_idx {
-            Some(ScopeIdx(parent_scope_idx)) => {
-                let parent_scope = vcd.all_scopes.get_mut(parent_scope_idx).unwrap();
-                parent_scope.child_scopes.push(curr_scope_idx);
-            }
-            None => vcd.root_scopes.push(curr_scope_idx),
+    // register this scope as a child of the current parent scope
+    // if there is a parent scope, or else we register this scope as
+    // root scope
+    match parent_scope_idx {
+        Some(ScopeIdx(parent_scope_idx)) => {
+            let parent_scope = vcd.all_scopes.get_mut(parent_scope_idx).unwrap();
+            parent_scope.child_scopes.push(curr_scope_idx);
         }
+        None => vcd.root_scopes.push(curr_scope_idx),
+    }
 
-        // add this scope to list of existing scopes
-        vcd.all_scopes.push(Scope {
-            name: scope_name.to_string(),
-            self_idx: curr_scope_idx,
-            child_signals: vec![],
-            child_scopes: vec![],
-        });
+    // add this scope to list of existing scopes
+    vcd.all_scopes.push(Scope {
+        name: scope_name.to_string(),
+        parent_idx: parent_scope_idx,
+        self_idx: curr_scope_idx,
+        child_signals: vec![],
+        child_scopes: vec![],
+    });
 
-        // $scope module reg_mag_i $end
-        //                         ^^^^ - end keyword
-        ident(word_reader, "$end")?;
+    // $scope module reg_mag_i $end
+    //                         ^^^^ - end keyword
+    ident(word_reader, "$end")?;
 
-        loop {
-            let (word, cursor) = next_word!(word_reader)?;
-            let ParseResult { matched, residual } = tag(word, "$");
-            match matched {
-                // we hope that this word starts with a `$`
-                "$" => {
-                    match residual {
-                        "scope" => {
-                            // recursive - parse inside of current scope tree
-                            parse_scopes_inner(
-                                word_reader,
-                                Some(curr_scope_idx),
-                                vcd,
-                                signal_map,
-                                &path,
-                            )?;
-                        }
-                        "var" => {
-                            parse_var(word_reader, curr_scope_idx, vcd, signal_map, &path)?;
-                        }
-                        "upscope" => {
-                            ident(word_reader, "$end")?;
+    loop {
+        let (word, cursor) = next_word!(word_reader)?;
+        let ParseResult { matched, residual } = tag(word, "$");
+        match matched {
+            // we hope that this word starts with a `$`
+            "$" => {
+                match residual {
+                    "scope" => {
+                        // recursive - parse inside of current scope tree
+                        parse_scopes_inner(word_reader, Some(curr_scope_idx), vcd, signal_map)?;
+                    }
+                    "var" => {
+                        parse_var(word_reader, curr_scope_idx, vcd, signal_map)?;
+                    }
+                    "upscope" => {
+                        ident(word_reader, "$end")?;
+                        break;
+                    }
+                    // we ignore comments
+                    "comment" => loop {
+                        if ident(word_reader, "$end").is_ok() {
                             break;
                         }
-                        // we ignore comments
-                        "comment" => loop {
-                            if ident(word_reader, "$end").is_ok() {
-                                break;
-                            }
-                        },
-                        _ => {
-                            let err = format!(
-                                "Error near {}:{}. \
-                                               found keyword `{residual}` but expected \
-                                               `$scope`, `$var`, `$comment`, or `$upscope` \
-                                               on {cursor:?}",
-                                file!(),
-                                line!()
-                            );
-                            return Err(err);
-                        }
+                    },
+                    _ => {
+                        let err = format!(
+                            "Error near {}:{}. \
+                                           found keyword `{residual}` but expected \
+                                           `$scope`, `$var`, `$comment`, or `$upscope` \
+                                           on {cursor:?}",
+                            file!(),
+                            line!()
+                        );
+                        return Err(err);
                     }
                 }
-                _ => {
-                    let err = format!(
-                        "Error near {}:{}. \
-                                      found keyword `{matched}` but \
-                                      expected `$` on {cursor:?}",
-                        file!(),
-                        line!()
-                    );
-                    return Err(err);
-                }
             }
-        }
-    } else {
-        // We'll be conservative and only allow new scopes in this case, and make the nameless
-        // scope completely transparent. I.e.
-        // $scope module a $end
-        //   $scope module $end
-        //     $scope module b $end
-        //       ...
-        //     $upscope
-        //   $upscope
-        // $upscope
-        // will create `a.b`
-        loop {
-            let (word, cursor) = next_word!(word_reader)?;
-            let ParseResult { matched, residual } = tag(word, "$");
-            match matched {
-                // we hope that this word starts with a `$`
-                "$" => {
-                    match residual {
-                        "scope" => {
-                            // recursive - parse inside of current scope tree
-                            parse_scopes_inner(
-                                word_reader,
-                                parent_scope_idx,
-                                vcd,
-                                signal_map,
-                                &path,
-                            )?;
-                        }
-                        "upscope" => {
-                            ident(word_reader, "$end")?;
-                            break;
-                        }
-                        // we ignore comments
-                        "comment" => loop {
-                            if ident(word_reader, "$end").is_ok() {
-                                break;
-                            }
-                        },
-                        _ => {
-                            let err = format!(
-                                "Error near {}:{}. \
-                                               found keyword `{residual}` in annonyoums scope but expected \
-                                               `$scope`, `$comment`, or `$upscope` \
-                                               on {cursor:?}",
-                                file!(),
-                                line!()
-                            );
-                            return Err(err);
-                        }
-                    }
-                }
-                _ => {
-                    let err = format!(
-                        "Error near {}:{}. \
-                                      found keyword `{matched}` but \
-                                      expected `$` on {cursor:?}",
-                        file!(),
-                        line!()
-                    );
-                    return Err(err);
-                }
+            _ => {
+                let err = format!(
+                    "Error near {}:{}. \
+                                  found keyword `{matched}` but \
+                                  expected `$` on {cursor:?}",
+                    file!(),
+                    line!()
+                );
+                return Err(err);
             }
         }
     }
@@ -444,13 +311,13 @@ fn parse_scopes_inner<R: std::io::Read>(
     Ok(())
 }
 
-pub(super) fn parse_scopes<R: std::io::Read>(
-    word_reader: &mut WordReader<R>,
-    vcd: &mut VCD,
+pub(super) fn parse_scopes<'a>(
+    word_reader: &mut WordReader,
+    vcd: &'a mut VCD,
     signal_map: &mut HashMap<String, SignalIdx>,
 ) -> Result<(), String> {
     // get the current word
-    let (word, _) = curr_word!(word_reader)?;
+    let (word, cursor) = curr_word!(word_reader)?;
 
     // we may have orphaned vars that occur before the first scope
     if word == "$var" {
@@ -476,7 +343,7 @@ pub(super) fn parse_scopes<R: std::io::Read>(
     }
 
     // now for the interesting part
-    parse_scopes_inner(word_reader, None, vcd, signal_map, &vec![])?;
+    parse_scopes_inner(word_reader, None, vcd, signal_map)?;
 
     // let err = format!("reached end of file without parser leaving {}", function_name!());
     let expected_keywords = ["$scope", "$enddefinitions"];
@@ -490,13 +357,13 @@ pub(super) fn parse_scopes<R: std::io::Read>(
 
         match word {
             "$scope" => {
-                parse_scopes_inner(word_reader, None, vcd, signal_map, &vec![])?;
+                parse_scopes_inner(word_reader, None, vcd, signal_map)?;
             }
             "$enddefinitions" => {
                 ident(word_reader, "$end")?;
                 break;
             }
-            "$comment" => {
+            "comment" => {
                 // although we don't store comments, we still need to advance the
                 // word_reader cursor to the end of the comment
                 loop {

src/vcd/parse/types.rs

@@ -1,27 +1,25 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
 #[derive(Debug)]
 pub(super) struct ParseResult<'a> {
-    pub(super) matched: &'a str,
-    pub(super) residual: &'a str,
-}
+    pub(super) matched : &'a str, 
+    pub(super) residual : &'a str}
 
 impl<'a> ParseResult<'a> {
-    pub(super) fn assert_match(&self) -> Result<&str, String> {
-        if self.matched.is_empty() {
-            Err("no match".to_string())
-        } else {
-            Ok(self.matched)
+
+    pub(super) fn assert_match(& self) -> Result<&str, String> {
+        if self.matched == "" {
+            return Err("no match".to_string())
+        }
+        else {
+            return Ok(self.matched)
         }
     }
 
-    pub(super) fn assert_residual(&self) -> Result<&str, String> {
-        if self.residual.is_empty() {
-            Err("no residual".to_string())
-        } else {
-            Ok(self.residual)
+    pub(super) fn assert_residual(& self) -> Result<&str, String> {
+        if self.residual == "" {
+            return Err("no residual".to_string())
+        }
+        else {
+            return Ok(self.residual)
         }
     }
-}
+}

src/vcd/reader.rs

@@ -1,10 +1,7 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
 use std::collections::VecDeque;
+use std::fs::File;
 use std::io;
-use std::io::BufRead;
+use std::io::prelude::*;
 use std::slice;
 use std::str;
 
@@ -15,8 +12,8 @@ pub(super) struct Word(pub(super) usize);
 #[derive(Debug, Clone)]
 pub(super) struct Cursor(pub(super) Line, pub(super) Word);
 
-pub(super) struct WordReader<R: io::Read> {
-    reader: io::BufReader<R>,
+pub(super) struct WordReader {
+    reader: io::BufReader<File>,
     eof: bool,
     buffers: Vec<String>,
     curr_line: usize,
@@ -24,11 +21,11 @@ pub(super) struct WordReader<R: io::Read> {
     curr_slice: Option<(*const u8, usize, Cursor)>,
 }
 
-impl<R: std::io::Read> WordReader<R> {
-    pub(super) fn new(file: R) -> WordReader<R> {
+impl WordReader {
+    pub(super) fn new(file: File) -> WordReader {
         let reader = io::BufReader::new(file);
         WordReader {
-            reader,
+            reader: reader,
             eof: false,
             buffers: vec![],
             curr_line: 0,

src/vcd/signal.rs

@@ -1,237 +1,81 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-use super::types;
-use super::types::SignalIdx;
-use num::BigUint;
+use super::{ScopeIdx, SignalIdx};
+use num::{BigUint, Zero};
 
 // Index to the least significant byte of a timestamp
 // value on the timeline
 #[derive(Debug, Copy, Clone)]
 pub struct LsbIdxOfTmstmpValOnTmln(pub(super) u32);
 
-#[derive(Debug, Eq, PartialEq, Clone)]
-pub enum SignalType {
-    Event,
+#[derive(Debug)]
+pub(super) enum SigType {
     Integer,
     Parameter,
     Real,
-    RealTime,
     Reg,
     Str,
-    Supply0,
-    Supply1,
-    Time,
-    Tri,
-    TriAnd,
-    TriOr,
-    TriReg,
-    Tri0,
-    Tri1,
-    WAnd,
     Wire,
-    WOr,
+    Tri1,
+    Time,
 }
 
-#[derive(Debug, PartialEq)]
-pub enum SignalValue {
+#[derive(Debug)]
+pub(super) enum TimelineQueryResults {
     BigUint(BigUint),
     String(String),
 }
 
-pub struct QueryResult<T> {
-    pub current: Option<(TimeStamp, T)>,
-    pub next: Option<TimeStamp>,
-}
-
-pub struct Signal<'a>(pub(super) &'a SignalEnum);
-
-impl<'a> Signal<'a> {
-    pub fn name(&self) -> String {
-        let Signal(signal_enum) = &self;
-        signal_enum.name()
-    }
-
-    pub fn name_with_index(&self) -> String {
-        let Signal(signal_enum) = &self;
-        signal_enum.name_with_index()
-    }
-
-    pub fn index(&self) -> Option<String> {
-        let Signal(signal_enum) = &self;
-        signal_enum.index()
-    }
-
-    pub fn path(&self) -> &[String] {
-        match self.0 {
-            SignalEnum::Data { path, .. } => path,
-            SignalEnum::Alias { path, .. } => path,
-        }
-    }
-
-    pub fn signal_type(&self) -> Option<&SignalType> {
-        let Signal(signal_enum) = &self;
-        signal_enum.signal_type()
-    }
-
-    pub fn real_idx(&self) -> SignalIdx {
-        match self.0 {
-            SignalEnum::Data { self_idx, .. } => *self_idx,
-            SignalEnum::Alias { signal_alias, .. } => *signal_alias,
-        }
-    }
-
-    pub fn num_bits(&self) -> Option<u32> {
-        let Signal(signal_enum) = &self;
-        signal_enum.bits_required()
-    }
-
-    // NOTE: (zoq) I am removing thse because they aren't used in Surfer so I can't test them
-    // properly
-    /*
-    pub fn query_string_val_on_tmln(
-        &self,
-        desired_time: &BigUint,
-        vcd: &types::VCD,
-    ) -> Result<String, SignalErrors> {
-        let Signal(signal_enum) = &self;
-        signal_enum
-            .query_string_val_on_tmln(desired_time, &vcd.tmstmps_encoded_as_u8s, &vcd.all_signals)
-            .map(|QueryResult{current, next: _}| current.map(|c| c.1))
-    }
-
-    pub fn query_num_val_on_tmln(
-        &self,
-        desired_time: &BigUint,
-        vcd: &types::VCD,
-    ) -> Result<Option<BigUint>, SignalErrors> {
-        let Signal(signal_enum) = &self;
-        signal_enum
-            .query_num_val_on_tmln(desired_time, &vcd.tmstmps_encoded_as_u8s, &vcd.all_signals)
-            .map(|QueryResult{current, next: _}| current.map(|c| c.1))
-    }
-    */
-
-    pub fn query_val_on_tmln(
-        &self,
-        desired_time: &BigUint,
-        vcd: &types::VCD,
-    ) -> Result<QueryResult<SignalValue>, SignalErrors> {
-        let Signal(signal_enum) = &self;
-        let num_query_out = signal_enum.query_num_val_on_tmln(
-            desired_time,
-            &vcd.tmstmps_encoded_as_u8s,
-            &vcd.all_signals,
-        );
-        let str_query_out = signal_enum.query_string_val_on_tmln(
-            desired_time,
-            &vcd.tmstmps_encoded_as_u8s,
-            &vcd.all_signals,
-        );
-
-        // Both num and str will return the newest value that is closest to
-        // the desired time. If both have valid values, select the most recent
-        // one
-        match (num_query_out, str_query_out) {
-            (Ok(num_result), Ok(str_result)) => {
-                let next = match (num_result.next, str_result.next) {
-                    (Some(n), Some(s)) => Some(n.min(s)),
-                    (Some(n), None) => Some(n),
-                    (None, Some(s)) => Some(s),
-                    (None, None) => None,
-                };
-
-                match (num_result.current, str_result.current) {
-                    (Some((num_time, num_value)), Some((str_time, str_value))) => {
-                        if num_time > str_time {
-                            Ok(QueryResult {
-                                current: Some((num_time, SignalValue::BigUint(num_value))),
-                                next,
-                            })
-                        } else {
-                            Ok(QueryResult {
-                                current: Some((str_time, SignalValue::String(str_value))),
-                                next,
-                            })
-                        }
-                    }
-                    (Some((num_time, num_val)), None) => Ok(QueryResult {
-                        current: Some((num_time, SignalValue::BigUint(num_val))),
-                        next,
-                    }),
-                    (None, Some((str_time, str_value))) => Ok(QueryResult {
-                        current: Some((str_time, SignalValue::String(str_value))),
-                        next,
-                    }),
-                    (None, None) => Ok(QueryResult {
-                        current: None,
-                        next,
-                    }),
-                }
-            }
-            (_e, Err(e)) => Err(e),
-            (Err(e), _e) => Err(e),
-        }
-    }
-}
-
 #[derive(Debug)]
-pub(super) enum SignalEnum {
+pub(super) enum Signal {
     Data {
         name: String,
-        path: Vec<String>,
-        signal_type: SignalType,
-        /// The optional [start:end] part of the signal name that is sometimes
-        /// added to signals
-        index: Option<String>,
-        /// I've seen a 0 bit signal parameter in a xilinx
-        /// simulation before that gets assigned 1 bit values.
-        /// I consider this to be bad behavior. We capture such
-        /// errors in the following type:
+        sig_type: SigType,
+        // I've seen a 0 bit signal parameter in a xilinx
+        // simulation before that gets assigned 1 bit values.
+        // I consider this to be bad behavior. We capture such
+        // errors in the following type:
         signal_error: Option<String>,
-        num_bits: Option<u32>,
-        num_bytes: Option<u16>,
-        /// TODO : may be able to remove self_idx
+        num_bits: Option<u16>,
+        num_bytes: Option<u8>,
+        // TODO : may be able to remove self_idx
         self_idx: SignalIdx,
-        /// A signal may take on a new value and hold that value
-        /// for sometime. We only need to record the value of a signal
-        /// when it changes(the is what VCDs tend to do).
-        /// A signal may need x amount of bytes to record its largest
-        /// possible value, so we record every single value of a given
-        /// signal as a sequence of x number of u8s.
-        /// For example, we might find that `my_signal.
-        /// nums_encoded_as_fixed_width_le_u8`
-        /// has two 32 bit values, namely, 1 and 2, encoded as follows:
-        /// my_signal.nums_encoded_as_fixed_width_le_u8 = vec![1u8, 0u8,
-        /// 0u8, 0u8, 2u8, 0u8, 0u8, 0u8];
+        // A signal may take on a new value and hold that value
+        // for sometime. We only need to record the value of a signal
+        // when it changes(the is what VCDs tend to do).
+        // A signal may need x amount of bytes to record its largest possible
+        // value, so we record every single value of a given signal as a sequence
+        // of x number of u8s.
+        // For example, we might find that `my_signal.nums_encoded_as_fixed_width_le_u8`
+        // has two 32 bit values, namely, 1 and 2, encoded as follows:
+        // my_signal.nums_encoded_as_fixed_width_le_u8 = vec![1u8, 0u8, 0u8, 0u8, 2u8, 0u8, 0u8, 0u8];
         nums_encoded_as_fixed_width_le_u8: Vec<u8>,
         string_vals: Vec<String>,
-        /// we could do Vec<(LsbIdxOfTmstmpValOnTmln, u8)>, but I
-        /// suspect that Vec<LsbIdxOfTmstmpValOnTmln> is more cache
-        /// friendly. We use ``LsbIdxOfTmstmpValOnTmln`` to index into
-        /// the LSB of a particular timestamp encoded as the
-        /// minimum length u8 sequence within
-        /// ``vcd.tmstmps_encoded_as_u8s``, and we use the values in
-        /// ``byte_len_of_num_tmstmp_vals_on_tmln`` to determine how
-        /// many u8 values a particular timestamp is composed of.
+        // we could do Vec<(LsbIdxOfTmstmpValOnTmln, u8)>, but I suspect that
+        // Vec<LsbIdxOfTmstmpValOnTmln> is more cache friendly.
+        // We use ``LsbIdxOfTmstmpValOnTmln`` to index into the LSB of a particular
+        // timestamp encoded as the minimu length u8 sequence within
+        // ``vcd.tmstmps_encoded_as_u8s``, and we use the values in
+        // ``byte_len_of_num_tmstmp_vals_on_tmln`` to determine how many u8 values
+        // a particular timestamp is composed of.
         lsb_indxs_of_num_tmstmp_vals_on_tmln: Vec<LsbIdxOfTmstmpValOnTmln>,
         byte_len_of_num_tmstmp_vals_on_tmln: Vec<u8>,
         byte_len_of_string_tmstmp_vals_on_tmln: Vec<u8>,
         lsb_indxs_of_string_tmstmp_vals_on_tmln: Vec<LsbIdxOfTmstmpValOnTmln>,
+        scope_parent: ScopeIdx,
     },
     Alias {
         name: String,
-        path: Vec<String>,
         signal_alias: SignalIdx,
     },
 }
 
 #[derive(Debug)]
-pub enum SignalErrors {
+pub(super) enum SignalErrors {
+    PreTimeline {
+        desired_time: BigUint,
+        timeline_start_time: BigUint,
+    },
     EmptyTimeline,
     TimelineNotMultiple,
-    StrTmlnLenMismatch,
     OrderingFailure {
         lhs_time: BigUint,
         mid_time: BigUint,
@@ -246,124 +90,20 @@ pub enum SignalErrors {
 type TimeStamp = BigUint;
 type SignalValNum = BigUint;
 
-// getter functions
-impl SignalEnum {
-    pub fn name(&self) -> String {
-        match self {
-            SignalEnum::Data { name, .. } => name,
-            SignalEnum::Alias { name, .. } => name,
-        }
-        .clone()
-    }
-
-    pub fn signal_type(&self) -> Option<&SignalType> {
-        match self {
-            SignalEnum::Data { signal_type, .. } => Some(signal_type),
-            // TODO: Follow aliases?
-            SignalEnum::Alias { .. } => None,
-        }
-        .clone()
-    }
-
-    pub fn name_with_index(&self) -> String {
-        match self {
-            SignalEnum::Data {
-                name, index: None, ..
-            } => format!("{name}"),
-            SignalEnum::Data {
-                name,
-                index: Some(size),
-                ..
-            } => format!("{name} {size}"),
-            SignalEnum::Alias { name, .. } => name.clone(),
-        }
-    }
-
-    pub fn index(&self) -> Option<String> {
-        match self {
-            SignalEnum::Data { index, .. } => index.clone(),
-            SignalEnum::Alias { .. } => None,
-        }
-    }
-}
-
-// helper functions ultimately used by Signal's query functions later on
-impl SignalEnum {
-    /// Computes the bytes required to store a signal's numerical value
-    /// using the num_bits which another function would provide from
-    /// the num_bits field of the Signal::Data variant.
-    pub(super) fn bytes_required(num_bits: u32, name: &String) -> Result<u16, String> {
+impl Signal {
+    pub(super) fn bytes_required(num_bits: u16, name: &String) -> Result<u8, String> {
         let bytes_required = (num_bits / 8) + if (num_bits % 8) > 0 { 1 } else { 0 };
-        let bytes_required = u16::try_from(bytes_required).map_err(|_| {
+        let bytes_required = u8::try_from(bytes_required).map_err(|_| {
             format!(
                 "Error near {}:{}. Signal {name} of length num_bits requires \
-                        {bytes_required} > 65536 bytes.",
+                        {bytes_required} > 256 bytes.",
                 file!(),
                 line!()
             )
         })?;
         Ok(bytes_required)
     }
-    /// This function takes an event_idx which(is used to index into the
-    /// global timeline field of a VCD struct instance) and computes
-    /// the time pointed at by event_idx.
-    /// This function also uses the same idx to index into the
-    /// string_vals field of an instance of the Signal::Data variant
-    ///  and gets a string value.
-    /// The function returns a tuple of the timestamp and string value.
-    fn time_and_str_val_at_event_idx(
-        &self,
-        event_idx: usize,
-        tmstmps_encoded_as_u8s: &Vec<u8>,
-    ) -> Result<(TimeStamp, &str), SignalErrors> {
-        let (
-            string_vals,
-            lsb_indxs_of_string_tmstmp_vals_on_tmln,
-            byte_len_of_string_tmstmp_vals_on_tmln,
-        ) = match self {
-            SignalEnum::Data {
-                string_vals,
-                lsb_indxs_of_string_tmstmp_vals_on_tmln,
-                byte_len_of_string_tmstmp_vals_on_tmln,
-                ..
-            } => Ok((
-                string_vals,
-                lsb_indxs_of_string_tmstmp_vals_on_tmln,
-                byte_len_of_string_tmstmp_vals_on_tmln,
-            )),
-            SignalEnum::Alias { .. } => Err(SignalErrors::PointsToAlias),
-        }?;
-
-        // get index
-        let LsbIdxOfTmstmpValOnTmln(timestamp_idx) =
-            lsb_indxs_of_string_tmstmp_vals_on_tmln[event_idx];
-        let timestamp_idx = timestamp_idx as usize;
-
-        if byte_len_of_string_tmstmp_vals_on_tmln.is_empty() {
-            return Err(SignalErrors::EmptyTimeline);
-        }
-
-        // form timestamp
-        let byte_len = byte_len_of_string_tmstmp_vals_on_tmln[event_idx] as usize;
-        let timestamp = &tmstmps_encoded_as_u8s[timestamp_idx..(timestamp_idx + byte_len)];
-        let timestamp = BigUint::from_bytes_le(timestamp);
-
-        // get signal value
-        let signal_val = string_vals[event_idx].as_str();
-
-        Ok((timestamp, signal_val))
-    }
-    /// This function takes an event_idx which(is used to index into the
-    /// global timeline field of a VCD struct instance) and computes
-    /// the time pointed at by event_idx.
-    /// This function also uses the same idx to index into the
-    /// nums_encoded_as_fixed_width_le_u8 and
-    /// byte_len_of_num_tmstmp_vals_on_tmln fields of an instance
-    /// of the Signal::Data variant to compute the signal's corresponding
-    /// numerical value at the time pointed at by event_didx.
-    /// The function returns a tuple of the timestamp and numerical
-    /// value.
-    fn time_and_num_val_at_event_idx(
+    pub(super) fn lookup_time_and_val(
         &self,
         event_idx: usize,
         tmstmps_encoded_as_u8s: &Vec<u8>,
@@ -374,7 +114,7 @@ impl SignalEnum {
             lsb_indxs_of_num_tmstmp_vals_on_tmln,
             byte_len_of_num_tmstmp_vals_on_tmln,
         ) = match self {
-            SignalEnum::Data {
+            Signal::Data {
                 num_bytes,
                 nums_encoded_as_fixed_width_le_u8,
                 lsb_indxs_of_num_tmstmp_vals_on_tmln,
@@ -386,7 +126,7 @@ impl SignalEnum {
                 lsb_indxs_of_num_tmstmp_vals_on_tmln,
                 byte_len_of_num_tmstmp_vals_on_tmln,
             )),
-            SignalEnum::Alias { .. } => Err(SignalErrors::PointsToAlias),
+            Signal::Alias { .. } => Err(SignalErrors::PointsToAlias),
         }?;
 
         // get index
@@ -409,161 +149,12 @@ impl SignalEnum {
 
         Ok((timestamp, signal_val))
     }
-
-    fn bits_required(&self) -> Option<u32> {
-        match self {
-            SignalEnum::Data { num_bits, .. } => *num_bits,
-            // TODO: Follow aliases?
-            SignalEnum::Alias { .. } => None,
-        }
-    }
-}
-
-// Val and string query functions.
-// Function that take in a desired time on the timeline for a
-// specific signal and return a numerical or string value in a Result,
-// or an error in a Result.
-impl SignalEnum {
-    pub fn query_string_val_on_tmln(
-        &self,
-        desired_time: &BigUint,
-        tmstmps_encoded_as_u8s: &Vec<u8>,
-        all_signals: &Vec<SignalEnum>,
-    ) -> Result<QueryResult<String>, SignalErrors> {
-        let signal_idx = match self {
-            Self::Data { self_idx, .. } => {
-                let SignalIdx(idx) = self_idx;
-                *idx
-            }
-            Self::Alias {
-                name: _,
-                signal_alias,
-                path: _,
-            } => {
-                let SignalIdx(idx) = signal_alias;
-                *idx
-            }
-        };
-
-        // if the signal idx points to data variant of the signal,
-        // extract:
-        // 1. the vector of string values
-        // 2. the vector of indices into timeline where events occur
-        //    for this signal
-        // else we propagate Err(..).
-        let (string_vals, lsb_indxs_of_string_tmstmp_vals_on_tmln) = match &all_signals[signal_idx]
-        {
-            SignalEnum::Data {
-                ref string_vals,
-                ref lsb_indxs_of_string_tmstmp_vals_on_tmln,
-                ..
-            } => Ok((string_vals, lsb_indxs_of_string_tmstmp_vals_on_tmln)),
-            SignalEnum::Alias { .. } => Err(SignalErrors::PointsToAlias),
-        }?;
-        // this signal should at least have some events, otherwise, trying to index into
-        // an empty vector later on would fail
-        if lsb_indxs_of_string_tmstmp_vals_on_tmln.is_empty() {
-            return Ok(QueryResult {
-                current: None,
-                next: None
-            });
-        }
-
-        // the vector of string timeline lsb indices should have the same
-        // length as the vector of string values
-        if string_vals.len() != lsb_indxs_of_string_tmstmp_vals_on_tmln.len() {
-            return Err(SignalErrors::StrTmlnLenMismatch);
-        }
-
-        // check if we're requesting a value that occurs before the recorded
-        // start of the timeline
-        let (timeline_start_time, _) =
-            self.time_and_str_val_at_event_idx(0, tmstmps_encoded_as_u8s)?;
-        if *desired_time < timeline_start_time {
-            return Ok(QueryResult {
-                current: None,
-                next: Some(timeline_start_time),
-            });
-        }
-
-        let mut lower_idx = 0usize;
-        let mut upper_idx = lsb_indxs_of_string_tmstmp_vals_on_tmln.len() - 1;
-        let (timeline_end_time, timeline_end_val) =
-            self.time_and_str_val_at_event_idx(upper_idx, tmstmps_encoded_as_u8s)?;
-
-        // check if we're requesting a value that occurs beyond the end of the timeline,
-        // if so, return the last value in this timeline
-        if *desired_time > timeline_end_time {
-            return Ok(QueryResult {
-                current: Some((timeline_end_time, timeline_end_val.to_string())),
-                next: None,
-            });
-        }
-
-        // This while loop is the meat of the lookup. Performance is log2(n),
-        // where n is the number of events on the timeline.
-        // We can assume that by the time we get here, that the desired_time
-        // is an event that occurs on the timeline, given that we handle any events
-        // occuring after or before the recorded tiimeline in the code above.
-        while lower_idx <= upper_idx {
-            let mid_idx = lower_idx + ((upper_idx - lower_idx) / 2);
-            let (curr_time, curr_val) =
-                self.time_and_str_val_at_event_idx(mid_idx, tmstmps_encoded_as_u8s)?;
-            let ordering = curr_time.cmp(desired_time);
-
-            match ordering {
-                std::cmp::Ordering::Less => {
-                    lower_idx = mid_idx + 1;
-                }
-                std::cmp::Ordering::Equal => {
-                    let next_time = if mid_idx < lsb_indxs_of_string_tmstmp_vals_on_tmln.len() - 1 {
-                        Some(
-                            self.time_and_str_val_at_event_idx(
-                                mid_idx + 1,
-                                tmstmps_encoded_as_u8s,
-                            )?
-                            .0,
-                        )
-                    } else {
-                        None
-                    };
-                    return Ok(QueryResult {
-                        current: Some((curr_time, curr_val.to_string())),
-                        next: next_time,
-                    });
-                }
-                std::cmp::Ordering::Greater => {
-                    upper_idx = mid_idx - 1;
-                }
-            }
-        }
-
-        let (left_time, left_val) =
-            self.time_and_str_val_at_event_idx(lower_idx - 1, tmstmps_encoded_as_u8s)?;
-        let (right_time, _) =
-            self.time_and_str_val_at_event_idx(lower_idx, tmstmps_encoded_as_u8s)?;
-
-        let ordered_left = left_time < *desired_time;
-        let ordered_right = *desired_time < right_time;
-        if !(ordered_left && ordered_right) {
-            return Err(SignalErrors::OrderingFailure {
-                lhs_time: left_time,
-                mid_time: desired_time.clone(),
-                rhs_time: right_time,
-            });
-        }
-
-        Ok(QueryResult {
-            current: Some((left_time, left_val.to_string())),
-            next: Some(right_time),
-        })
-    }
     pub fn query_num_val_on_tmln(
         &self,
-        desired_time: &BigUint,
+        desired_time: BigUint,
         tmstmps_encoded_as_u8s: &Vec<u8>,
-        all_signals: &Vec<SignalEnum>,
-    ) -> Result<QueryResult<BigUint>, SignalErrors> {
+        all_signals: &Vec<Signal>,
+    ) -> Result<BigUint, SignalErrors> {
         let signal_idx = match self {
             Self::Data { self_idx, .. } => {
                 let SignalIdx(idx) = self_idx;
@@ -571,7 +162,6 @@ impl SignalEnum {
             }
             Self::Alias {
                 name: _,
-                path: _,
                 signal_alias,
             } => {
                 let SignalIdx(idx) = signal_alias;
@@ -579,16 +169,9 @@ impl SignalEnum {
             }
         };
 
-        // if the signal idx points to data variant of the signal,
-        // extract:
-        // 1. the vector of LE u8 compressed values
-        // 2. the vector of indices into timeline where events occur
-        //    for this signal
-        // 3. the number of bytes per value for this signal
-        // else we propagate Err(..).
         let (nums_encoded_as_fixed_width_le_u8, lsb_indxs_of_num_tmstmp_vals_on_tmln, num_bytes) =
             match &all_signals[signal_idx] {
-                SignalEnum::Data {
+                Signal::Data {
                     num_bytes,
                     ref nums_encoded_as_fixed_width_le_u8,
                     ref lsb_indxs_of_num_tmstmp_vals_on_tmln,
@@ -603,15 +186,12 @@ impl SignalEnum {
                         num_bytes,
                     ))
                 }
-                SignalEnum::Alias { .. } => Err(SignalErrors::PointsToAlias),
+                Signal::Alias { .. } => Err(SignalErrors::PointsToAlias),
             }?;
         // this signal should at least have some events, otherwise, trying to index into
         // an empty vector later on would fail
         if lsb_indxs_of_num_tmstmp_vals_on_tmln.is_empty() {
-            return Ok(QueryResult {
-                current: None,
-                next: None
-            });
+            return Err(SignalErrors::EmptyTimeline);
         }
 
         // assertion that value_sequence is a proper multiple of
@@ -626,32 +206,32 @@ impl SignalEnum {
         if nums_encoded_as_fixed_width_le_u8.len()
             != (lsb_indxs_of_num_tmstmp_vals_on_tmln.len() * (bytes_required as usize))
         {
+            dbg!((
+                nums_encoded_as_fixed_width_le_u8.len(),
+                (lsb_indxs_of_num_tmstmp_vals_on_tmln.len() * (bytes_required as usize))
+            ));
             return Err(SignalErrors::TimelineNotMultiple);
         }
 
         // check if we're requesting a value that occurs before the recorded
         // start of the timeline
-        let (timeline_start_time, _) =
-            self.time_and_num_val_at_event_idx(0, tmstmps_encoded_as_u8s)?;
-        if *desired_time < timeline_start_time {
-            return Ok(QueryResult {
-                current: None,
-                next: Some(timeline_start_time),
+        let (timeline_start_time, _) = self.lookup_time_and_val(0, tmstmps_encoded_as_u8s)?;
+        if desired_time < timeline_start_time {
+            return Err(SignalErrors::PreTimeline {
+                desired_time: desired_time,
+                timeline_start_time: timeline_start_time,
             });
         }
 
         let mut lower_idx = 0usize;
         let mut upper_idx = lsb_indxs_of_num_tmstmp_vals_on_tmln.len() - 1;
         let (timeline_end_time, timeline_end_val) =
-            self.time_and_num_val_at_event_idx(upper_idx, tmstmps_encoded_as_u8s)?;
+            self.lookup_time_and_val(upper_idx, tmstmps_encoded_as_u8s)?;
 
         // check if we're requesting a value that occurs beyond the end of the timeline,
         // if so, return the last value in this timeline
-        if *desired_time > timeline_end_time {
-            return Ok(QueryResult {
-                current: Some((timeline_end_time, timeline_end_val)),
-                next: None,
-            });
+        if desired_time > timeline_end_time {
+            return Ok(timeline_end_val);
         }
 
         // This while loop is the meat of the lookup. Performance is log2(n),
@@ -662,29 +242,15 @@ impl SignalEnum {
         while lower_idx <= upper_idx {
             let mid_idx = lower_idx + ((upper_idx - lower_idx) / 2);
             let (curr_time, curr_val) =
-                self.time_and_num_val_at_event_idx(mid_idx, tmstmps_encoded_as_u8s)?;
-            let ordering = curr_time.cmp(desired_time);
+                self.lookup_time_and_val(mid_idx, tmstmps_encoded_as_u8s)?;
+            let ordering = curr_time.cmp(&desired_time);
 
             match ordering {
                 std::cmp::Ordering::Less => {
                     lower_idx = mid_idx + 1;
                 }
                 std::cmp::Ordering::Equal => {
-                    let next_time = if mid_idx < lsb_indxs_of_num_tmstmp_vals_on_tmln.len() - 1 {
-                        Some(
-                            self.time_and_num_val_at_event_idx(
-                                mid_idx + 1,
-                                tmstmps_encoded_as_u8s,
-                            )?
-                            .0,
-                        )
-                    } else {
-                        None
-                    };
-                    return Ok(QueryResult {
-                        current: Some((curr_time, curr_val)),
-                        next: next_time,
-                    });
+                    return Ok(curr_val);
                 }
                 std::cmp::Ordering::Greater => {
                     upper_idx = mid_idx - 1;
@@ -693,23 +259,19 @@ impl SignalEnum {
         }
 
         let (left_time, left_val) =
-            self.time_and_num_val_at_event_idx(lower_idx - 1, tmstmps_encoded_as_u8s)?;
-        let (right_time, _) =
-            self.time_and_num_val_at_event_idx(lower_idx, tmstmps_encoded_as_u8s)?;
+            self.lookup_time_and_val(lower_idx - 1, tmstmps_encoded_as_u8s)?;
+        let (right_time, _) = self.lookup_time_and_val(lower_idx, tmstmps_encoded_as_u8s)?;
 
-        let ordered_left = left_time < *desired_time;
-        let ordered_right = *desired_time < right_time;
+        let ordered_left = left_time < desired_time;
+        let ordered_right = desired_time < right_time;
         if !(ordered_left && ordered_right) {
             return Err(SignalErrors::OrderingFailure {
                 lhs_time: left_time,
-                mid_time: desired_time.clone(),
+                mid_time: desired_time,
                 rhs_time: right_time,
             });
         }
 
-        return Ok(QueryResult {
-            current: Some((left_time, left_val)),
-            next: Some(right_time),
-        });
+        return Ok(left_val);
     }
 }

src/vcd/types.rs

@@ -1,19 +1,11 @@
-// use crate::Signal;
+use super::Signal;
+use chrono::prelude::*;
 
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-use super::signal::{Signal, SignalEnum};
-use chrono::prelude::{DateTime, Utc};
-use num::BigUint;
-use std::fmt;
+#[derive(Debug)]
+pub(super) struct Version(pub String);
 
-#[derive(Debug, Clone)]
-pub struct Version(pub String);
-
-#[derive(Debug, Clone, Copy, Eq, PartialEq)]
-pub enum Timescale {
+#[derive(Debug)]
+pub(super) enum Timescale {
     Fs,
     Ps,
     Ns,
@@ -23,38 +15,25 @@ pub enum Timescale {
     Unit,
 }
 
-impl fmt::Display for Timescale {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match self {
-            Timescale::Fs => write!(f, "fs"),
-            Timescale::Ps => write!(f, "ps"),
-            Timescale::Ns => write!(f, "ns"),
-            Timescale::Us => write!(f, "μs"),
-            Timescale::Ms => write!(f, "ms"),
-            Timescale::S => write!(f, "s"),
-            Timescale::Unit => write!(f, "unit"),
-        }
-    }
-}
-
 #[derive(Debug)]
-pub struct Metadata {
-    pub date: Option<DateTime<Utc>>,
-    pub version: Option<Version>,
-    pub timescale: (Option<u32>, Timescale),
+pub(super) struct Metadata {
+    pub(super) date: Option<DateTime<Utc>>,
+    pub(super) version: Option<Version>,
+    pub(super) timescale: (Option<u32>, Timescale),
 }
 
 // We do a lot of arena allocation in this codebase.
-#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
-pub struct ScopeIdx(pub usize);
+#[derive(Debug, Copy, Clone)]
+pub(super) struct ScopeIdx(pub(super) usize);
 
-#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
-pub struct SignalIdx(pub usize);
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub(super) struct SignalIdx(pub(super) usize);
 
 #[derive(Debug)]
 pub(super) struct Scope {
     pub(super) name: String,
 
+    pub(super) parent_idx: Option<ScopeIdx>,
     pub(super) self_idx: ScopeIdx,
 
     pub(super) child_signals: Vec<SignalIdx>,
@@ -63,7 +42,7 @@ pub(super) struct Scope {
 
 #[derive(Debug)]
 pub struct VCD {
-    pub metadata: Metadata,
+    pub(super) metadata: Metadata,
     // Since we only need to store values when there is an actual change
     // in the timeline, we keep a vector that stores the time at which an
     // event occurs. Time t is always stored/encoded as the minimum length sequence
@@ -74,62 +53,38 @@ pub struct VCD {
     // vector of u8s that constitute a timestamp value. Signals don't have to
     // keep track of all timestamp values, a given signal only needs to keep
     // track of the timestamps at which the given signal value changes.
-    pub(super) tmstmps_encoded_as_u8s: Vec<u8>,
-    pub(super) all_signals: Vec<SignalEnum>,
+    pub tmstmps_encoded_as_u8s: Vec<u8>,
+    pub(super) all_signals: Vec<Signal>,
     pub(super) all_scopes: Vec<Scope>,
     pub(super) root_scopes: Vec<ScopeIdx>,
-    pub(super) largest_timestamp: Option<BigUint>,
 }
 
 impl VCD {
-    pub fn root_scopes_by_idx(&self) -> Vec<ScopeIdx> {
-        self.root_scopes.clone()
-    }
-    pub fn child_scopes_by_idx(&self, scope_idx: ScopeIdx) -> Vec<ScopeIdx> {
-        let ScopeIdx(idx) = scope_idx;
-        let scope = &self.all_scopes[idx];
-        scope.child_scopes.clone()
-    }
-    pub fn get_children_signal_idxs(&self, scope_idx: ScopeIdx) -> Vec<SignalIdx> {
-        let ScopeIdx(idx) = scope_idx;
-        let scope = &self.all_scopes[idx];
-        scope.child_signals.clone()
-    }
-    pub fn scope_name_by_idx(&self, scope_idx: ScopeIdx) -> &String {
-        let ScopeIdx(idx) = scope_idx;
-        let scope = &self.all_scopes[idx];
-        &scope.name
-    }
-    pub fn signal_from_signal_idx(&self, idx: SignalIdx) -> Signal<'_> {
-        let SignalIdx(idx) = idx;
-        let signal_enum = &self.all_signals[idx];
-        return Signal(signal_enum);
-    }
-    /// We take in a Signal and attempt to de-alias that signal if it is of
+    /// We take in a Signal and attempt to dereference that signal if it is of
     /// variant ``Signal::Alias``. If it is of variant ``Signal::Alias`` and points to
     /// another alias, that's an error. Otherwise, we return the ``Signal::Data``
     /// pointed to by the ``Signal::Alias``.
     /// If the Signal is of varint ``Signal::Data``, then that can be returned directly.
-    pub(super) fn dealiasing_signal_idx_to_signal_lookup_mut<'a>(
+    pub(super) fn try_dereference_alias_mut<'a>(
         &'a mut self,
         idx: &SignalIdx,
-    ) -> Result<&'a mut SignalEnum, String> {
+    ) -> Result<&'a mut Signal, String> {
         // get the signal pointed to be SignalIdx from the arena
         let SignalIdx(idx) = idx;
         let signal = &self.all_signals[*idx];
 
         // dereference signal if Signal::Alias, or keep idx if Signal::Data
         let signal_idx = match signal {
-            SignalEnum::Data { self_idx, .. } => *self_idx,
-            SignalEnum::Alias { signal_alias, .. } => *signal_alias,
+            Signal::Data { self_idx, .. } => *self_idx,
+            Signal::Alias { name, signal_alias } => *signal_alias,
         };
 
         // Should now  point to Signal::Data variant, or else there's an error
         let SignalIdx(idx) = signal_idx;
         let signal = self.all_signals.get_mut(idx).unwrap();
         match signal {
-            SignalEnum::Data { .. } => Ok(signal),
-            SignalEnum::Alias { .. } => Err(format!(
+            Signal::Data { .. } => Ok(signal),
+            Signal::Alias { .. } => Err(format!(
                 "Error near {}:{}. A signal alias shouldn't \
                  point to a signal alias.",
                 file!(),
@@ -137,8 +92,31 @@ impl VCD {
             )),
         }
     }
+    pub(super) fn try_dereference_alias<'a>(
+        &'a self,
+        idx: &SignalIdx,
+    ) -> Result<&'a Signal, String> {
+        // get the signal pointed to be SignalIdx from the arena
+        let SignalIdx(idx) = idx;
+        let signal = &self.all_signals[*idx];
 
-    pub fn max_timestamp(&self) -> &Option<BigUint> {
-        &self.largest_timestamp
+        // dereference signal if Signal::Alias, or keep idx if Signal::Data
+        let signal_idx = match signal {
+            Signal::Data { self_idx, .. } => *self_idx,
+            Signal::Alias { name, signal_alias } => *signal_alias,
+        };
+
+        // Should now  point to Signal::Data variant, or else there's an error
+        let SignalIdx(idx) = signal_idx;
+        let signal = self.all_signals.get(idx).unwrap();
+        match signal {
+            Signal::Data { .. } => Ok(signal),
+            Signal::Alias { .. } => Err(format!(
+                "Error near {}:{}. A signal alias shouldn't \
+                 point to a signal alias.",
+                file!(),
+                line!()
+            )),
+        }
     }
 }

src/vcd/utilities.rs

@@ -1,16 +1,8 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
 #[derive(Debug)]
 pub(super) enum BinaryParserErrTypes {
     XValue,
     ZValue,
     UValue,
-    HValue,
-    LValue,
-    DashValue,
-    WValue,
     OtherValue(char),
     TooLong,
 }
@@ -38,15 +30,11 @@ fn base2_str_to_byte(word: &[u8]) -> Result<u8, BinaryParserErrTypes> {
 
     for (idx, chr) in word.iter().rev().enumerate() {
         match chr {
-            b'1' => val |= bit_lut[idx],
+            b'1' => val = bit_lut[idx] | val,
             b'0' => {}
             b'x' | b'X' => return Err(BinaryParserErrTypes::XValue),
             b'z' | b'Z' => return Err(BinaryParserErrTypes::ZValue),
             b'u' | b'U' => return Err(BinaryParserErrTypes::UValue),
-            b'l' | b'L' => return Err(BinaryParserErrTypes::LValue),
-            b'h' | b'H' => return Err(BinaryParserErrTypes::HValue),
-            b'w' | b'W' => return Err(BinaryParserErrTypes::WValue),
-            b'-' => return Err(BinaryParserErrTypes::DashValue),
             _ => return Err(BinaryParserErrTypes::OtherValue(*chr as char)),
         }
     }
@@ -73,13 +61,13 @@ pub(super) fn binary_str_to_vec_u8(binary_str: &str) -> Result<Vec<u8>, BinaryPa
         if head_idx < 8 {
             head_idx = 0
         } else {
-            head_idx -= 8;
+            head_idx = head_idx - 8;
         }
 
         if tail_idx < 8 {
             tail_idx = 0
         } else {
-            tail_idx -= 8;
+            tail_idx = tail_idx - 8;
         }
     }
     Ok(vec_u8)

tests/files.rs

@@ -1,77 +0,0 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-
-// TODO: we should eventually be able to only test on just
-// the files const
-pub const FILES: [&str; 31] = [
-    "./tests/vcd-files/aldec/SPI_Write.vcd",
-    "./tests/vcd-files/ghdl/alu.vcd",
-    "./tests/vcd-files/ghdl/idea.vcd",
-    "./tests/vcd-files/ghdl/pcpu.vcd",
-    "./tests/vcd-files/gtkwave-analyzer/perm_current.vcd",
-    "./tests/vcd-files/icarus/CPU.vcd",
-    "./tests/vcd-files/icarus/rv32_soc_TB.vcd",
-    "./tests/vcd-files/icarus/test1.vcd",
-    "./tests/vcd-files/model-sim/CPU_Design.msim.vcd",
-    "./tests/vcd-files/model-sim/clkdiv2n_tb.vcd",
-    "./tests/vcd-files/my-hdl/Simple_Memory.vcd",
-    "./tests/vcd-files/my-hdl/sigmoid_tb.vcd",
-    "./tests/vcd-files/my-hdl/top.vcd",
-    "./tests/vcd-files/ncsim/ffdiv_32bit_tb.vcd",
-    "./tests/vcd-files/quartus/mipsHardware.vcd",
-    "./tests/vcd-files/quartus/wave_registradores.vcd",
-    "./tests/vcd-files/questa-sim/dump.vcd",
-    "./tests/vcd-files/questa-sim/test.vcd",
-    "./tests/vcd-files/riviera-pro/dump.vcd",
-    "./tests/vcd-files/systemc/waveform.vcd",
-    "./tests/vcd-files/treadle/GCD.vcd",
-    "./tests/vcd-files/vcs/Apb_slave_uvm_new.vcd",
-    "./tests/vcd-files/vcs/datapath_log.vcd",
-    "./tests/vcd-files/vcs/processor.vcd",
-    "./tests/vcd-files/verilator/swerv1.vcd",
-    "./tests/vcd-files/verilator/vlt_dump.vcd",
-    "./tests/vcd-files/vivado/iladata.vcd",
-    "./tests/vcd-files/xilinx_isim/test.vcd",
-    "./tests/vcd-files/xilinx_isim/test1.vcd",
-    // TODO : add signal ignore list to handle bitwidth mismatches
-    "./tests/vcd-files/xilinx_isim/test2x2_regex22_string1.vcd",
-    "./tests/vcd-files/scope_with_comment.vcd",
-];
-
-pub const GOOD_DATE_FILES: [&str; 24] = [
-    "./test-vcd-files/aldec/SPI_Write.vcd",
-    "./test-vcd-files/ghdl/alu.vcd",
-    "./test-vcd-files/ghdl/idea.vcd",
-    "./test-vcd-files/ghdl/pcpu.vcd",
-    "./test-vcd-files/gtkwave-analyzer/perm_current.vcd",
-    "./test-vcd-files/icarus/CPU.vcd",
-    "./test-vcd-files/icarus/rv32_soc_TB.vcd",
-    "./test-vcd-files/icarus/test1.vcd",
-    "./test-vcd-files/model-sim/CPU_Design.msim.vcd",
-    "./test-vcd-files/model-sim/clkdiv2n_tb.vcd",
-    "./test-vcd-files/my-hdl/Simple_Memory.vcd",
-    "./test-vcd-files/my-hdl/sigmoid_tb.vcd",
-    "./test-vcd-files/my-hdl/top.vcd",
-    "./test-vcd-files/questa-sim/dump.vcd",
-    "./test-vcd-files/questa-sim/test.vcd",
-    "./test-vcd-files/riviera-pro/dump.vcd",
-    "./test-vcd-files/vcs/Apb_slave_uvm_new.vcd",
-    "./test-vcd-files/vcs/datapath_log.vcd",
-    "./test-vcd-files/vcs/processor.vcd",
-    "./test-vcd-files/verilator/swerv1.vcd",
-    "./test-vcd-files/verilator/vlt_dump.vcd",
-    "./test-vcd-files/xilinx_isim/test.vcd",
-    "./test-vcd-files/xilinx_isim/test1.vcd",
-    "./test-vcd-files/xilinx_isim/test2x2_regex22_string1.vcd",
-];
-
-pub const BAD_DATE_FILES: [&str; 6] = [
-    "./test-vcd-files/ncsim/ffdiv_32bit_tb.vcd",
-    "./test-vcd-files/quartus/mipsHardware.vcd",
-    "./test-vcd-files/quartus/wave_registradores.vcd",
-    "./test-vcd-files/systemc/waveform.vcd",
-    "./test-vcd-files/treadle/GCD.vcd",
-    "./test-vcd-files/vivado/iladata.vcd",
-];

tests/integration_test.rs

@@ -1,22 +0,0 @@
-// Copyright (C) 2022 Yehowshua Immanuel
-// This program is distributed under both the GPLV3 license
-// and the YEHOWSHUA license, both of which can be found at
-// the root of the folder containing the sources for this program.
-use std::fs::File;
-
-mod files;
-use files::*;
-
-#[test]
-fn parse_all_VCDs() {
-    // see if we can parse all signal trees successfully
-    for file_name in FILES {
-        let file = File::open(file_name).unwrap();
-        let vcd = fastwave_backend::parse_vcd(file);
-
-        if !vcd.is_ok() {
-            dbg!(file_name);
-            vcd.unwrap();
-        }
-    }
-}

tests/vcd-files/scope_with_comment.vcd

@@ -1,296 +0,0 @@
-$date
-	Sat Dec 26 15:33:14 2020
-$end
-$version
-	ModelSim Version 10.5b
-$end
-$timescale
-	1ns
-$end
-
-$scope module clkdiv2n_tb $end
-$comment foo $end
-$var reg 1 ! clk $end
-$var reg 1 " reset $end
-$var wire 1 # clk_out $end
-
-$scope module t1 $end
-$var parameter 32 $ WIDTH $end
-$var parameter 32 % N $end
-$var wire 1 & clk $end
-$var wire 1 ' reset $end
-$var wire 1 # clk_out $end
-$var reg 3 ( r_reg [2:0] $end
-$var wire 1 ) r_nxt [2] $end
-$var wire 1 * r_nxt [1] $end
-$var wire 1 + r_nxt [0] $end
-$var reg 1 , clk_track $end
-$upscope $end
-$comment foo $end
-$upscope $end
-$comment foo $end
-$enddefinitions $end
-#0
-$comment foo $end
-$dumpvars
-0!
-x"
-bx (
-x,
-b11 $
-b110 %
-x#
-x+
-x*
-x)
-x'
-0&
-$end
-#5
-1"
-1'
-b0 (
-0,
-1+
-0*
-0)
-0#
-#10
-1!
-1&
-#15
-0"
-0'
-#20
-0!
-0&
-#30
-1!
-1&
-b1 (
-0+
-1*
-#40
-0!
-0&
-#50
-1!
-1&
-b10 (
-1+
-#60
-0!
-0&
-#70
-1!
-1&
-b11 (
-0+
-0*
-1)
-#80
-0!
-0&
-#90
-1!
-1&
-b100 (
-1+
-#100
-0!
-0&
-#110
-1!
-1&
-b101 (
-0+
-1*
-#120
-0!
-0&
-#130
-1!
-1&
-b0 (
-1,
-1+
-0*
-0)
-1#
-#140
-0!
-0&
-#150
-1!
-1&
-b1 (
-0+
-1*
-#160
-0!
-0&
-#170
-1!
-1&
-b10 (
-1+
-#180
-0!
-0&
-#190
-1!
-1&
-b11 (
-0+
-0*
-1)
-#200
-0!
-0&
-#210
-1!
-1&
-b100 (
-1+
-#220
-0!
-0&
-#230
-1!
-1&
-b101 (
-0+
-1*
-#240
-0!
-0&
-#250
-1!
-1&
-b0 (
-0,
-1+
-0*
-0)
-0#
-#260
-0!
-0&
-#270
-1!
-1&
-b1 (
-0+
-1*
-#280
-0!
-0&
-#290
-1!
-1&
-b10 (
-1+
-#300
-0!
-0&
-#310
-1!
-1&
-b11 (
-0+
-0*
-1)
-#320
-0!
-0&
-#330
-1!
-1&
-b100 (
-1+
-#340
-0!
-0&
-#350
-1!
-1&
-b101 (
-0+
-1*
-#360
-0!
-0&
-#370
-1!
-1&
-b0 (
-1,
-1+
-0*
-0)
-1#
-#380
-0!
-0&
-#390
-1!
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-b1 (
-0+
-1*
-#400
-0!
-0&
-#410
-1!
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-b10 (
-1+
-#420
-0!
-0&
-#430
-1!
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-b11 (
-0+
-0*
-1)
-#440
-0!
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-#450
-1!
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-b100 (
-1+
-#460
-0!
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-#470
-1!
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-0+
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-#480
-0!
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-#490
-1!
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-b0 (
-0,
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-#500
-0!
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-#510
-1!
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-b1 (
-0+
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