# File test/lexertest.rb, line 63
  def test_nextchars
    lex = JSON::Lexer.new("some_string")
    str = lex.nextchars(4)
    assert(str == 'some', "nextchars doesn't work correctly")
    assert_raises(RuntimeError, "exception not raised for substring bounds error") {
      lex.nextchars(10)
    }
  end