1 files changed, 59 insertions, 0 deletions
diff --git a/build-aux/Makefile.once.head/zz-mod.mk b/build-aux/Makefile.once.head/zz-mod.mk
new file mode 100644
index 0000000..95d251d
--- /dev/null
+++ b/build-aux/Makefile.once.head/zz-mod.mk
@@ -0,0 +1,59 @@
+# Copyright (C) 2016  Luke Shumaker
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+mod.mod.description = Display information about Autothing modules
+mod.mod.depends += quote
+define mod.mod.doc
+# Inputs:
+#   - Files           : `$(topsrcdir)/build-aux/Makefile.*/??-*.mk`
+#   - Global variable : `mod.*.description`
+#   - Global variable : `mod.*.depends`
+#   - Global variable : `mod.*.files`
+#   - Global variable : `mod.*.doc`
+# Outputs:
+#   - Directory variable : `at.targets`
+#   - .PHONY Target      : `$(outdir)/at-variables-local`
+#   - .PHONY Target      : `$(outdir)/at-variables-global`
+#   - .PHONY Target      : `$(outdir)/at-variables`
+#   - .PHONY Target      : `$(outdir)/at-variables/%`
+#   - .PHONY Target      : `$(outdir)/at-values`
+#   - .PHONY Target      : `$(outdir)/at-values/%`
+#   - .PHONY Target      : `$(outdir)/at-modules`
+#   - .PHONY Target      : `$(outdir)/at-modules/%`
+#   - .PHONY Target      : `$(outdir)/at-noop`
+#
+# TODO: prose documentation
+endef
+mod.mod.doc := $(value mod.mod.doc)
+
+# The trickery that is _mod.empty/_mod.space is from §6.2 of the GNU Make
+# manual, "The Two Flavors of Variables".
+_mod.empty :=
+_mod.space := $(_mod.empty) #
+undefine _mod.empty
+# _mod.rest is equivalent to GMSL rest.
+_mod.rest = $(wordlist 2,$(words $1),$1)
+
+_mod.file2mod = $(foreach _mod.tmp,$(patsubst %.mk,%,$(notdir $1)),$(subst $(_mod.space),-,$(call _mod.rest,$(subst -, ,$(_mod.tmp)))))
+
+_mod.modules := $(sort $(call _mod.file2mod,$(wildcard $(topsrcdir)/build-aux/Makefile.*/??-*.mk)))
+undefine _mod.rest
+undefine _mod.file2mod
+
+$(eval $(foreach _mod.tmp,$(_mod.modules),\
+  mod.$(_mod.tmp).description ?=$(at.nl)\
+  mod.$(_mod.tmp).depends ?=$(at.nl)\
+  mod.$(_mod.tmp).files ?=$(at.nl)\
+  mod.$(_mod.tmp).doc ?=$(at.nl)))