testPrefix (ExpressionParserTest)

    # File test/src/expression_test.rb, line 57
      def testPrefix
        parser = whitespace.many_ >> int.prefix(negate) << eof
        assertParser(' - -3 ', 3, parser)
        assertParser(' 3', 3, parser)
        assertParser('3 ', 3, parser)
        assertParser('-3', -3, parser)
        assertError(' - -', 'integer expected', parser, 4)
        assertError(' - -5 3', 'EOF expected', parser, 6)
      end