Cleaned up code for retrieving method parameters.

The use of Array#map would require the use of Array#compact to get rid of
NilClass values in the parameters collection. An easier (and probably a bit
faster way) of doing this is to simply use Array#each and push values into
another Array.

Signed-off-by: Yorick Peterse <yorickpeterse@gmail.com>

kernel/common/compiled_code.rb

@@ -510,26 +510,30 @@ def get_metadata(key)
     ##
     # For Method#parameters
     def parameters
+      params = []
+
+      return params unless respond_to?(:local_names)
+
       m = required_args - post_args
       o = m + total_args - required_args
       p = o + post_args
       p += 1 if splat
 
-      params = local_names.each_with_index.map do |name, i|
+      local_names.each_with_index do |name, i|
         if i < m
-          [:req, name]
+          params << [:req, name]
         elsif i < o
-          [:opt, name]
+          params << [:opt, name]
         elsif splat == i
-          [:rest, name]
+          params << [:rest, name]
         elsif i < p
-          [:req, name]
+          params << [:req, name]
         elsif block == i
-          [:block, name]
+          params << [:block, name]
         end
       end
 
-      return params.compact
+      return params
     end
 
     ##

kernel/common/method.rb

@@ -262,28 +262,7 @@ def source_location
   end
 
   def parameters
-    return [] unless @executable.respond_to? :local_names
-
-    m = @executable.required_args - @executable.post_args
-    o = m + @executable.total_args - @executable.required_args
-    p = o + @executable.post_args
-    p += 1 if @executable.splat
-
-    params = @executable.local_names.each_with_index.map do |name, i|
-      if i < m
-        [:req, name]
-      elsif i < o
-        [:opt, name]
-      elsif @executable.splat == i
-        [:rest, name]
-      elsif i < p
-        [:req, name]
-      elsif @executable.block == i
-        [:block, name]
-      end
-    end
-
-    return params.compact
+    return @executable.respond_to?(:parameters) ? @executable.parameters : []
   end
 
   def owner