feat(3p/bqn-libs): init

Change-Id: Ibbc152e782027de6eda9fba5c628f3d4fc227370
Reviewed-on: https://cl.tvl.fyi/c/depot/+/13019
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
Autosubmit: sterni <sternenseemann@systemli.org>

third_party/bqn-libs/default.nix

@@ -0,0 +1,39 @@
+# - Standalone, importable files are installed to $out/lib/*.bqn.
+#   They have no external dependencies, but do import each other (via relative paths).
+# - Documentation to $out/share/doc/bqn-libs.
+#
+# Note: This packaging is ad hoc and tentative. No way to handle BQN dependencies
+# for depot (or Nix, for that matter) has been proposed yet. If you have ideas /
+# want to work on this, talk to sterni.
+# TODO(sterni): Find out whether any work towards a BQN package manager exists
+#
+# The problem is that BQN is sort of like Nix: It only has the notion of direct
+# file imports. Unlike Nix, however, it doesn't even have a builtin notion of a
+# search path, so the design space is unconstrained. The most obvious solution
+# would be to implement some kind of search part ourselves. Unfortunately, there
+# is no portable way to access environment variables in BQN at the moment.
+{ depot, pkgs, lib, ... }:
+
+let
+  src = pkgs.fetchFromGitHub {
+    inherit (depot.third_party.sources.bqn-libs)
+      repo
+      owner
+      sha256
+      rev
+      ;
+  };
+in
+
+pkgs.runCommandNoCC "bqn-libs-${builtins.substring 0 7 src.rev}"
+{
+  nativeBuildInputs = [
+    pkgs.cbqn
+  ];
+  meta.license = lib.licenses.bsd0;
+} ''
+  BQN "${src}/test/main.bqn"
+
+  install -Dm644 "${src}/"*.bqn -t "$out/lib"
+  install -Dm644 "${src}/LICENSE" -t "$out/share/doc/bqn-libs"
+''