case CharCode.ExclamationMark:
const isTripleEq = this._match(CharCode.Equals); // eat last `=` if `!==`
this._tokens.push({ type: TokenType.NotEq, offset: this._start, isTripleEq });
this._addToken(TokenType.Neg);
}
case CharCode.SingleQuote: this._quotedString(); break;