Method parseLabelledStatement

src/parser.ts:2507–2547

()

    // https://tc39.github.io/ecma262/#sec-labelled-statements

    parseLabelledStatement(): Node.LabeledStatement | Node.ExpressionStatement {
        const node = this.createNode();
        const expr = this.parseExpression();

        let statement: Node.ExpressionStatement | Node.LabeledStatement;
        if ((expr.type === Syntax.Identifier) && this.match(':')) {
            this.nextToken();

            const id = expr as Node.Identifier;
            const key = '$' + id.name;
            if (Object.prototype.hasOwnProperty.call(this.context.labelSet, key)) {
                this.throwError(Messages.Redeclaration, 'Label', id.name);
            }

            this.context.labelSet[key] = true;
            let body: Node.Statement;
            if (this.matchKeyword('class')) {
                this.tolerateUnexpectedToken(this.lookahead);
                body = this.parseClassDeclaration();
            } else if (this.matchKeyword('function')) {
                const token = this.lookahead;
                const declaration = this.parseFunctionDeclaration();
                if (this.context.strict) {
                    this.tolerateUnexpectedToken(token, Messages.StrictFunction);
                } else if (declaration.generator) {
                    this.tolerateUnexpectedToken(token, Messages.GeneratorInLegacyContext);
                }
                body = declaration;
            } else {
                body = this.parseStatement();
            }
            delete this.context.labelSet[key];

            statement = new Node.LabeledStatement(id, body);
        } else {
            this.consumeSemicolon();
            statement = new Node.ExpressionStatement(expr);
        }

        return this.finalize(node, statement);
    }

    // https://tc39.github.io/ecma262/#sec-throw-statement