cheatsheets/makefile.md

Var assignment

JS_COMPRESSOR := $(uglify)

# Safe assignment
prefix ?= /usr/local

Magic variables

$^   -- dependencies
$@   -- the thing to be built

$@   -- Rule target
$%   -- Target member name ('foo' in 'foo.c' for '%.c')
$^   -- Prerequisites (all, without duplication)
$+   -- Prerequisites (all, with duplication)
$?   -- Prerequisites (new ones)
$|   -- Prerequisites (order-only?)
$<   -- Prerequisite (first)
$*   -- Basename without extension of the target (?)

Cool stuff

	gitdir ?= $(shell git --exec-path)
	gitver ?= $(word 3,$(shell git --version))

Find files

FILES = $(shell find images -name "*")

$(patsubst images/%, assets/%, $(shell find images -name "*"))

Substitutions

# Same
	$(SOURCE:.cpp=.o)
	$(patsubst %.cpp, %.c, $(SOURCES))

$(strip $(string_var))

$(filter %.less, $(files))
$(filter-out %.less, $(files))

Executing

JS_COMPRESSOR := $(uglify)

docs:
  $(JS_COMPRESSOR) file.js

Building files

	%.o: %.c
		ffmpeg -i $< > $@   # Input and output
		foo $^

Default task

	default:
		@echo "hello."
  @false