Self-documenting Makefile experiment

git-svn-id: file:///srv/svn/repo/aya/trunk@97 cec141ff-132a-4243-88a5-ce187bd62f94

Makefile

@@ -8,16 +8,24 @@ DATE ?= `date -u +%F`
 GOOS ?= `${GO} env GOOS`
 VERSION ?= 1.0I+${REV}
 REV ?= `svn info --show-item revision || git rev-list --all | wc -l`
-build:
+
+all: help
+
+build: ## Build
 	${GO} build ${GOFLAGS} ./cmd/aya
-clean:
+clean: ## Remove built artifact(s)
 	rm -f aya
+help:
+	@printf "Aya v%s\n" ${VERSION}
+	@printf "Build targets: \n"
+	@printf "\n"
+	@awk 'BEGIN {FS = ":.*## "}; /^[a-zA-Z0-9_.%-]+:.*## / {printf "  %-12s%s\n", $$1, $$2}' ${MAKEFILE}
 pre-install:
 	mkdir -p ${DESTDIR}${BINDIR}
 	mkdir -p ${DESTDIR}${MANDIR}/man1
-install:
+install: pre-install ## Copy the built artifact(s) and manual pages into the system
 	install -m0755 aya ${DESTDIR}${BINDIR}
 	install -m0644 aya.1 ${DESTDIR}${MANDIR}/man1
-uninstall:
+uninstall: ## Remove the built artifact(s) and manual pages from the system
 	rm -f ${DESTDIR}${BINDIR}/aya
 	rm -f ${DESTDIR}${MANDIR}/man1/aya.1