1 files changed, 24 insertions, 0 deletions
diff --git a/tool/lrama/lib/lrama/grammar/binding.rb b/tool/lrama/lib/lrama/grammar/binding.rb
new file mode 100644
index 0000000000..e5ea3fb037
--- /dev/null
+++ b/tool/lrama/lib/lrama/grammar/binding.rb
@@ -0,0 +1,24 @@
+module Lrama
+  class Grammar
+    class Binding
+      attr_reader :actual_args, :count
+
+      def initialize(parameterizing_rule, actual_args)
+        @parameters = parameterizing_rule.parameters
+        @actual_args = actual_args
+        @parameter_to_arg = @parameters.zip(actual_args).map do |param, arg|
+          [param.s_value, arg]
+        end.to_h
+      end
+
+      def resolve_symbol(symbol)
+        if symbol.is_a?(Lexer::Token::InstantiateRule)
+          resolved_args = symbol.args.map { |arg| resolve_symbol(arg) }
+          Lrama::Lexer::Token::InstantiateRule.new(s_value: symbol.s_value, location: symbol.location, args: resolved_args, lhs_tag: symbol.lhs_tag)
+        else
+          @parameter_to_arg[symbol.s_value] || symbol
+        end
+      end
+    end
+  end
+end