nixpkgs/pkgs/lib/composable-derivation.nix
Marc Weber b56ed35851 replacing applyAndFun by lib.defaultOverridableDelayableArgs
applyAndFun has a bug resulting in the same arg beeing added more than
once when using a concatenating merge function for the attr set.

I've tried giving the function a name "overridableDelayableArgs" which
resembles its usage much more.

important refactoring:
  applyAndFun had .fun and .funMerge only when passing the merge
  function lib.mergeOrApply

  composableDerivation {
    initial = {
      ...
    };
  }

to

  overridableDelayableArgs has always .replace and .merge
  composableDerivation {} {
    ...
  }

svn path=/nixpkgs/trunk/; revision=14428
2009-03-06 23:21:28 +00:00

53 lines
1.8 KiB
Nix

{lib, pkgs} :
let inherit (lib) nv nvs; in
{
# see for example:
# - development/interpreters/php_configurable/default.nix
# - .. search composableDerivation in all-packages.nix ..
#
# You should be able to override anything you like easily
# grep the mailinglist by title "python proposal" (dec 08)
# -> http://mail.cs.uu.nl/pipermail/nix-dev/2008-December/001571.html
# to see why this got complicated when using all its features
# TODO add newer example using new syntax (kernel derivation proposal -> mailinglist)
composableDerivation = {
mkDerivation ? pkgs.stdenv.mkDerivation,
# list of functions to be applied before defaultOverridableDelayableArgs removes removeAttrs names
# prepareDerivationArgs handles derivation configurations
applyPreTidy ? [ lib.prepareDerivationArgs ],
# consider adding addtional elements by derivation.merge { removeAttrs = ["elem"]; };
removeAttrs ? ["cfg" "flags"]
}: (lib.defaultOverridableDelayableArgs ( a: mkDerivation a)
{
inherit applyPreTidy removeAttrs;
}).merge;
# some utility functions
# use this function to generate flag attrs for prepareDerivationArgs
# E nable D isable F eature
edf = {name, feat ? name, enable ? {}, disable ? {} , value ? ""}:
nvs name {
set = {
configureFlags = ["--enable-${feat}${if value == "" then "" else "="}${value}"];
} // enable;
unset = {
configureFlags = ["--disable-${feat}"];
} // disable;
};
# same for --with and --without-
# W ith or W ithout F eature
wwf = {name, feat ? name, enable ? {}, disable ? {}, value ? ""}:
nvs name {
set = {
configureFlags = ["--with-${feat}${if value == "" then "" else "="}${value}"];
} // enable;
unset = {
configureFlags = ["--without-${feat}"];
} // disable;
};
}