diff options
Diffstat (limited to 'pkgs')
| -rw-r--r-- | pkgs/lib/default-unstable.nix | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/pkgs/lib/default-unstable.nix b/pkgs/lib/default-unstable.nix index e5df0d40ac6..ff50cbf3756 100644 --- a/pkgs/lib/default-unstable.nix +++ b/pkgs/lib/default-unstable.nix @@ -17,7 +17,6 @@ rec { if list == [] then nul else op (head list) (fold op nul (tail list)); - # Concatenate a list of lists. concatLists = @@ -198,6 +197,7 @@ rec { catAttrs = attr : l : fold ( s : l : if (__hasAttr attr s) then [(__getAttr attr s)] ++ l else l) [] l; flattenSet = set : map ( attr : __getAttr attr set) (__attrNames set); + mapIf = cond : f : fold ( x : l : if (cond x) then [(f x)] ++ l else l) []; # Marc 2nd proposal: (not everything has been tested in detail yet..) # One example showing how to use mandatory dependencies [1], default flags [2], .. @@ -218,7 +218,7 @@ rec { # alternativeAddOn = { cfgOption = "--enable-add-ons-alt"; blocks = ["addOns", "addOns2"]; }; # justAOption = { }; # }; - # co = chosenOptions flagDescr args args.flags; + # co = chooseOptionsByFlags flagDescr ["libpng", "libjpg"] args; #in args.stdenv.mkDerivation { @@ -256,7 +256,17 @@ rec { # flags = { flagName = true/ false for each attribute in flagDescr # ... } - chosenOptions = flagDescr : args : flags : + # optionals is a list of dependency names. If passed as attribute in args they'll be automatically added + # to flags and flagDescr ( optionalName = { buildInputs = optionalName } ) + chooseOptionsByFlags = flagDescr : optionals : args : + let givenOptionals = listToAttrs + (mapIf ( a : (__hasAttr a args) ) + ( x: av x { buildInputs = x; } ) + optionals ); + fd = flagDescr // givenOptionals; + in chooseOptionsByFlags2 fd args ( getAttr ["flags"] [] args ++ (__attrNames givenOptionals ) ); + + chooseOptionsByFlags2 = flagDescr : args : flags : let # helper function collectFlags = state : flags : |