Adding 'yacas', a CAS implemented in C++.

svn path=/nixpkgs/trunk/; revision=23074

pkgs/applications/science/math/yacas/default.nix

···
+{stdenv, fetchurl, perl}: 
+
+stdenv.mkDerivation rec {
+  name = "yacas-1.2.2";
+
+  src = fetchurl {
+    url = "http://yacas.sourceforge.net/backups/${name}.tar.gz";
+    sha256 = "1dmafm3w0lm5w211nwkfzaid1rvvmgskz7k4500pjhgdczi5sd78";
+  };
+
+  # Perl is only for the documentation
+  buildInputs = [ perl ];
+
+  patches = [ ./gcc43.patch ];
+
+  meta = { 
+      description = "Easy to use, general purpose Computer Algebra System";
+      homepage = http://yacas.sourceforge.net/;
+      license = "GPLv2+";
+      maintainers = with stdenv.lib.maintainers; [viric];
+      platforms = with stdenv.lib.platforms; all;
+  };
+}

pkgs/top-level/all-packages.nix

···
     withX = true;
   };
 
+  yacas = callPackage ../applications/science/math/yacas { };
+
   ### SCIENCE / MISC
 
   golly = callPackage ../applications/science/misc/golly { };