example-spa-elm-app/frontend/Makefile

SRC_FILES := $(shell find src -name "*.elm")

all: elm.min.js

.PHONY: elm.min.js serve

ifeq ($(DEBUG)$(RELEASE),) # Both are empty
$(error You must set exactly one of DEBUG=1 or RELEASE=1)
endif

ifeq ($(DEBUG)$(RELEASE),11) # Both are set
$(error Both DEBUG and RELEASE cannot be set at the same time)
endif

elm.min.js:
ifeq ($(DEBUG),1)
	./build.sh --debug src/Main.elm
else ifeq ($(RELEASE),1)
	./build.sh --optimize src/Main.elm
endif

serve:
ifeq ($(DEBUG),1)
	elm-go src/Main.elm \
		--dir=../public \
		--port=8000 \
		--start-page=../public/index.html \
		--host=localhost \
		--proxy-prefix=/ \
		--proxy-host=http://localhost:8080 \
		-- \
		--debug \
		--output=../public/elm.min.js
else ifeq ($(RELEASE),1)
	$(error Cannot use serve target with RELEASE=1)
endif

clean:
	rm elm.js elm.min.js