diff --git a/lib/synvert/core.rb b/lib/synvert/core.rb
index ee767049..2d7b3261 100644
--- a/lib/synvert/core.rb
+++ b/lib/synvert/core.rb
@@ -77,4 +77,5 @@ module Synvert
   PARSER_PARSER = 'parser'
   SYNTAX_TREE_PARSER = 'syntax_tree'
   PRISM_PARSER = 'prism'
+  ALL_PARSERS = [PARSER_PARSER, SYNTAX_TREE_PARSER, PRISM_PARSER].freeze
 end
diff --git a/lib/synvert/core/rewriter.rb b/lib/synvert/core/rewriter.rb
index ef53b1b5..d364e463 100644
--- a/lib/synvert/core/rewriter.rb
+++ b/lib/synvert/core/rewriter.rb
@@ -201,7 +201,7 @@ def reset
     # @option strategy [String] 'allow_insert_at_same_position'
     def configure(options)
       @options = @options.merge(options)
-      if options[:parser] && ![Synvert::PARSER_PARSER, Synvert::SYNTAX_TREE_PARSER, Synvert::PRISM_PARSER].include?(options[:parser])
+      if options[:parser] && !Synvert::ALL_PARSERS.include?(options[:parser])
         raise Errors::ParserNotSupported.new("Parser #{options[:parser]} not supported")
       end
     end