diff --git a/lib/trivial.nix b/lib/trivial.nix index 21642ca0bdc..25ce35570fd 100644 --- a/lib/trivial.nix +++ b/lib/trivial.nix @@ -98,4 +98,19 @@ rec { */ importJSON = path: builtins.fromJSON (builtins.readFile path); + + /* See https://github.com/NixOS/nix/issues/749. Eventually we'd like these + to expand to Nix builtins that carry metadata so that Nix can filter out + the INFO messages without parsing the message string. + + Usage: + { + foo = lib.warn "foo is deprecated" oldFoo; + } + + TODO: figure out a clever way to integrate location information from + something like __unsafeGetAttrPos. + */ + warn = msg: builtins.trace "WARNING: ${msg}"; + info = msg: builtins.trace "INFO: ${msg}"; }