diff --git a/lib/racc/parser-text.rb b/lib/racc/parser-text.rb
index 0579f4ce9b..63ac2e368b 100644
--- a/lib/racc/parser-text.rb
+++ b/lib/racc/parser-text.rb
@@ -262,11 +262,11 @@ module Racc
     #     def next_token
     #       @q.shift
     #     end
-    class_eval %{
+    class_eval <<~RUBY, __FILE__, __LINE__ + 1
     def do_parse
       #{Racc_Main_Parsing_Routine}(_racc_setup(), false)
     end
-    }
+    RUBY
 
     # The method to fetch next token.
     # If you use #do_parse method, you must implement #next_token.
@@ -324,11 +324,11 @@ module Racc
     #
     # RECEIVER#METHOD_ID is a method to get next token.
     # It must 'yield' the token, which format is [TOKEN-SYMBOL, VALUE].
-    class_eval %{
+    class_eval <<~RUBY, __FILE__, __LINE__ + 1
     def yyparse(recv, mid)
       #{Racc_YY_Parse_Method}(recv, mid, _racc_setup(), false)
     end
-    }
+    RUBY
 
     def _racc_yyparse_rb(recv, mid, arg, c_debug)
       action_table, action_check, action_default, action_pointer,