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/*
  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;
      inherit drvAttrs;
    };

  outputToAttrListElement = outputName: {
    name = outputName;
    value = commonAttrs // {
      outPath = builtins.getAttr outputName strict;
      drvPath = strict.drvPath;
      type = "derivation";
      inherit outputName;
    };
  };

  outputsList = map outputToAttrListElement outputs;
in
(builtins.head outputsList).value