Basic specs for the XPath compiler

lib/oga/xpath/compiler.rb

@@ -1,7 +1,7 @@
 module Oga
   module XPath
     ##
-    # Compiling of XPath ASTs into Ruby source code.
+    # Compiling of XPath ASTs into Ruby code.
     #
     # The Compiler class can be used to turn an XPath AST into Ruby source code
     # that can be executed to match XML nodes in a given input document/element.
@@ -9,6 +9,15 @@ module Oga
     # recompiling the same expression over and over again.
     #
     class Compiler
+      ##
+      # Compiles an XPath AST into a Ruby Proc.
+      #
+      # @param [AST::Node] ast
+      # @return [Proc]
+      #
+      def compile(ast)
+
+      end
     end # Compiler
   end # XPath
 end # Oga