  lex: function(text) {
    this.text = text;
    this.index = 0;
    this.tokens = [];

    while (this.index < this.text.length) {
      var ch = this.text.charAt(this.index);
      if (ch === '"' || ch === '\'') {
        this.readString(ch);
      } else if (this.isNumber(ch) || ch === '.' && this.isNumber(this.peek())) {
        this.readNumber();
      } else if (this.isIdentifierStart(this.peekMultichar())) {
        this.readIdent();
      } else if (this.is(ch, '(){}[].,;:?')) {
        this.tokens.push({index: this.index, text: ch});
        this.index++;
      } else if (this.isWhitespace(ch)) {
        this.index++;
      } else {
        var ch2 = ch + this.peek();
        var ch3 = ch2 + this.peek(2);
        var op1 = OPERATORS[ch];
        var op2 = OPERATORS[ch2];
        var op3 = OPERATORS[ch3];
        if (op1 || op2 || op3) {
          var token = op3 ? ch3 : (op2 ? ch2 : ch);
          this.tokens.push({index: this.index, text: token, operator: true});
          this.index += token.length;
        } else {
          this.throwError('Unexpected next character ', this.index, this.index + 1);
        }
      }
    }
    return this.tokens;
  },
The software constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.