Last active
October 9, 2025 07:48
-
-
Save ruittenb/5d2d281237385276f49652b9b9f6d5a1 to your computer and use it in GitHub Desktop.
Makefile target for automatically generating help
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| ############################################################################ | |
| # | |
| # This code automatically creates a table of Makefile targets and short descriptions. | |
| # Descriptions should be added in the Makefile itself: | |
| # | |
| # '##' after a target is used for target descriptions | |
| # '##@' at the start of a line is used for header lines. | |
| # | |
| # See the examples below. | |
| # | |
| # The awk option '-v tab=10' can be changed to indent the second column of the output. | |
| # | |
| ##@ This is heading text, which is shown on a separate line. | |
| ##@ Heading text may be \ | |
| extended across lines. | |
| ##@ Heading text may contain\n- newlines\n- by specifying them with\n- backslash-n\n | |
| # This is just any comment and its continuation. \ | |
| It will not be parsed by 'make help'. | |
| ############################################################################ | |
| # | |
| # Readable version, with '$' replaced with makefile-style '$$': | |
| # | |
| # @awk -v tab=10 ' | |
| # BEGIN { | |
| # FS = ":.*## "; | |
| # buffer = ""; | |
| # color = "\033[36m"; | |
| # nocolor = "\033[0m"; | |
| # indent = " "; | |
| # usage(); | |
| # } | |
| # function trim(str) { | |
| # gsub(/[ \t]+$$/, "", str); | |
| # gsub(/^[ \t]+/, "", str); | |
| # return str; | |
| # } | |
| # function spout(target, desc) { | |
| # printf "%s%s%-" tab "s%s%s\n", indent, color, trim(target), nocolor, desc; | |
| # } | |
| # function usage() { | |
| # printf "\nUsage:\n%smake %s<target>%s\n\nRecognized targets:\n", indent, color, nocolor; | |
| # } | |
| # /\\$$/ { | |
| # gsub(/\\$$/, ""); | |
| # buffer = buffer $$0; | |
| # next; | |
| # } | |
| # buffer { | |
| # $$0 = buffer $$0; | |
| # buffer = ""; | |
| # } | |
| # /^[-a-zA-Z0-9*%_. ]+:.*?## / { | |
| # pad = sprintf("\n%" tab "s" indent, ""); | |
| # gsub(/\\n/, pad); | |
| # spout($$1, $$2); | |
| # } | |
| # /^##@ / { | |
| # gsub(/\\n/, "\n"); | |
| # printf "\n%s\n", substr($$0, 5); | |
| # } | |
| # END { | |
| # print ""; | |
| # } | |
| # ' $(MAKEFILE_LIST) # v1.51 | |
| ############################################################################ | |
| # | |
| # Concise version. Copy this block over to your own Makefile: | |
| .PHONY: help # See https://gist.github.com/ruittenb/5d2d281237385276f49652b9b9f6d5a1 | |
| help: ## Print help for each target | |
| @awk -v tab=10 'BEGIN { FS = ":.*## "; buffer = ""; color = "\033[36m"; nocolor = "\033[0m"; indent = " "; usage(); } function trim(str) { gsub(/[ \t]+$$/, "", str); gsub(/^[ \t]+/, "", str); return str; } function spout(target, desc) { printf "%s%s%-" tab "s%s%s\n", indent, color, trim(target), nocolor, desc; } function usage() { printf "\nUsage:\n%smake %s<target>%s\n\nRecognized targets:\n", indent, color, nocolor; } /\\$$/ { gsub(/\\$$/, ""); buffer = buffer $$0; next; } buffer { $$0 = buffer $$0; buffer = ""; } /^[-a-zA-Z0-9*%_. ]+:.*?## / { pad = sprintf("\n%" tab "s" indent, ""); gsub(/\\n/, pad); spout($$1, $$2); } /^##@ / { gsub(/\\n/, "\n"); printf "\n%s\n", substr($$0, 5) } END { print "" }' $(MAKEFILE_LIST) # v1.51 | |
| ############################################################################ | |
| # | |
| ##@ Example targets: | |
| show1: ## This is a description for show1, no prerequisites | |
| show2: prereq1 prereq2 ## This is a description for show2, with compact prerequisites | |
| show3: prereq1 \ | |
| prereq2 ## This is a description for show3, with continuation prerequisites | |
| show4: ## This is a description for show4 \ | |
| and its continuation, no prerequisites | |
| show5: prereq1 prereq2 ## This is a description for show5 \ | |
| and its continuation, with compact prerequisites | |
| show6: prereq1 \ | |
| prereq2 ## This is a description for show6 \ | |
| and its continuation, with continuation prerequisites | |
| ##@ None of these should be printed: | |
| noshow1: # This is just any comment, which will not be parsed by 'make help' | |
| noshow2: prereq1 prereq2 # This is just any comment, which will not be parsed by 'make help' | |
| noshow3: prereq1 \ | |
| prereq2 # This is just any comment, which will not be parsed by 'make help' | |
| noshow4: # This is just any comment and its continuation. \ | |
| It will not be parsed by 'make help'. | |
| noshow5: prereq1 prereq2 # This is just any comment and its continuation. \ | |
| It will not be parsed by 'make help'. | |
| noshow6: prereq1 \ | |
| prereq2 # This is just any comment and its continuation. \ | |
| It will not be parsed by 'make help'. | |
| # Makefile directives | |
| .DEFAULT_GOAL:=help | |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment