Method scanQuestion

packages/compiler/src/expression_parser/lexer.ts:537–556

(start: number)

  }

  private scanQuestion(start: number): Token {
    this.advance();
    let operator = '?';
    // `a ?? b` or `a ??= b`.
    if (this.peek === chars.$QUESTION) {
      operator += '?';
      this.advance();

      // @ts-expect-error
      if (this.peek === chars.$EQ) {
        operator += '=';
        this.advance();
      }
    } else if (this.peek === chars.$PERIOD) {
      // `a?.b`
      operator += '.';
      this.advance();
    }
    return newOperatorToken(start, this.index, operator);
  }

  private scanTemplateLiteralPart(start: number): Token {
    let buffer = '';