tvl-depot/corepkgs/derivation.nix
Eelco Dolstra 83647f4ef1 * Simplify the implementation of "derivation" a bit: lift out the
common attribution so that they're evaluated only once, etc.  Note
  that the default output is now the first element of the "outputs"
  attribute, rather than the first element of the sorted list of
  outputs.  This seems more user-friendly.
2012-01-04 11:04:19 +00:00

24 lines
706 B
Nix
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* This is the implementation of the derivation builtin function.
It's actually a wrapper around the derivationStrict primop. */
drvAttrs @ { outputs ? [ "out" ], ... }:
let
strict = derivationStrict drvAttrs;
commonAttrs = drvAttrs // (builtins.listToAttrs outputsList) // { all = map (x: x.value) outputsList; };
outputToAttrListElement = outputName:
{ name = outputName;
value = commonAttrs // {
outPath = builtins.getAttr outputName strict;
drvPath = strict.drvPath;
type = "derivation";
currentOutput = outputName;
};
};
outputsList = map outputToAttrListElement outputs;
in (builtins.head outputsList).value