anchor.diff:  { stdenv
   , fetchurl
  +, lib
   
   , atkmm
   , cairomm
  
positive.code: }:
  
  let
    inherit (stdenv.lib)
      boolEn;
  
    source = (import ./sources.nix { })."${channel}";
  
negative.code:     };
    };
  
    meta = with lib; {
      description = "C++ interface for GTK+";
      homepage = http://gtkmm.org/;
      license = licenses.lgpl2Plus;
  