lib/dentaku/tokenizer.rb in dentaku-1.2.1 vs lib/dentaku/tokenizer.rb in dentaku-1.2.2

@@ -8,10 +8,10 @@
     RPAREN = TokenMatcher.new(:grouping, :close)
 
     def tokenize(string)
       @nesting = 0
       @tokens  = []
-      input    = string.dup
+      input    = string.to_s.dup
 
       until input.empty?
         raise "parse error at: '#{ input }'" unless TokenScanner.scanners.any? do |scanner|
           scanned, input = scan(input, scanner)
           scanned