change builder VARIABLE_DEFAULTS constant to default_variables() class method

lib/rscons/builders/cc.rb

@@ -1,13 +1,15 @@
 module Rscons
   class CC < Builder
-    VARIABLE_DEFAULTS = {
+    def self.default_variables(env)
-      'CC' => 'gcc',
+      {
-      'CFLAGS' => [],
+        'CC' => 'gcc',
-      'CPPFLAGS' => [],
+        'CFLAGS' => [],
-      'OBJSUFFIX' => '.o',
+        'CPPFLAGS' => [],
-      'CEXTS' => ['.c'],
+        'OBJSUFFIX' => '.o',
-      'CCCOM' => ['$CC', '-c', '-o', '$TARGET', '$CPPFLAGS', '$CFLAGS', '$SOURCES']
+        'CEXTS' => ['.c'],
-    }
+        'CCCOM' => ['$CC', '-c', '-o', '$TARGET', '$CPPFLAGS', '$CFLAGS', '$SOURCES']
+      }
+    end
 
     def self.produces?(env, suffix)
       suffix == env['OBJSUFFIX']

lib/rscons/builders/program.rb

@@ -1,14 +1,16 @@
 module Rscons
   class Program < Builder
-    VARIABLE_DEFAULTS = {
+    def self.default_variables(env)
-      'LD' => nil,
+      {
-      'OBJSUFFIX' => '.o',
+        'LD' => nil,
-      'LIBSUFFIX' => '.a',
+        'OBJSUFFIX' => '.o',
-      'LDFLAGS' => [],
+        'LIBSUFFIX' => '.a',
-      'LIBPATHS' => [],
+        'LDFLAGS' => [],
-      'LIBS' => [],
+        'LIBPATHS' => [],
-      'LDCOM' => ['$LD', '-o', '$TARGET', '$LDFLAGS', '$SOURCES', '-L$[LIBPATHS]', '-l$[LIBS]']
+        'LIBS' => [],
-    }
+        'LDCOM' => ['$LD', '-o', '$TARGET', '$LDFLAGS', '$SOURCES', '-L$[LIBPATHS]', '-l$[LIBS]']
+      }
+    end
 
     def run(env, target, sources)
       sources = [sources] if sources.is_a?(String)

lib/rscons/environment.rb

@@ -25,7 +25,7 @@ module Rscons
 
     def add_builder(builder_class)
       @builders[builder_class.to_s.split(':').last] = builder_class
-      var_defs = builder_class.const_get('VARIABLE_DEFAULTS')
+      var_defs = builder_class.default_variables(self)
       if var_defs
         var_defs.each_pair do |var, val|
           unless @variables.has_key?(var)