Method expect

src/parser.js:551–557

Consumes the current token if it matches the provided one, otherwise throws

(token)

  /** Consumes the current token if it matches the provided one, otherwise throws */
  expect(token) {
    if (this.tkn === token) {
      this.nextToken();
    } else {
      this.err(`Missing expected token ${TokenValues[token & T$TokenMask]}`, this.idx);
    }
  }
}

// todo: we're missing a few here (https://tc39.github.io/ecma262/#table-34)