init Makefile

1 files changed, 37 insertions, 0 deletions

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..7960aab
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,37 @@
+# Makefile for Cabal packages in stockholm[0].
+# [0]: http://cgit.cd.krebsco.de/stockholm
+
+pkg-name := $(basename $(wildcard *.cabal))
+
+ifneq ($(words $(pkg-name)),1)
+$(error pkg-name is not a single word but '$(pkg-name)')
+endif
+
+.ONESHELL:
+.SHELLFLAGS := -efu -c
+
+export STOCKHOLM := $(HOME)/stockholm
+nix-shell-flags := -I nixpkgs="$$STOCKHOLM"
+
+# make V=1 to enable verbose output
+ifeq ($(V),1)
+nix-shell-flags += -v
+endif
+
+# This is basically what load-env[1] did, which is mostly dead.  Eventually
+# this should also become a wrapper for entering a development environment.
+# Notice that setting HOME is required for project-local GHCi history[2].  And
+# as we have to do it anyway, we're also reusing it for other stuff.
+# [1]: http://cgit.cd.krebsco.de/load-env
+# [2]: https://ghc.haskell.org/trac/ghc/ticket/9089
+.PHONY: shell
+shell: shell.nix
+	@verbose() { echo "$$*" >&2; "$$@"; }
+	verbose export HOME="$$HOME"/.env-home/$(pkg-name)
+	test -d "$$HOME" || verbose mkdir -p -m 0700 "$$HOME"
+	! test -f "$$HOME"/profile || verbose . "$$HOME"/profile
+	export HISTFILE="$$HOME"/histfile HISTSIZE=100000
+	verbose nix-shell $(nix-shell-flags) --command 'exec ghci'
+
+shell.nix: $(pkg-name).cabal
+	cabal2nix --shell . > $@