Method parseConditionalExpression

src/parser.ts:1524–1545

()

    // https://tc39.github.io/ecma262/#sec-conditional-operator

    parseConditionalExpression(): Node.Expression {
        const startToken = this.lookahead;

        let expr = this.inheritCoverGrammar(this.parseBinaryExpression);
        if (this.match('?')) {
            this.nextToken();

            const previousAllowIn = this.context.allowIn;
            this.context.allowIn = true;
            const consequent = this.isolateCoverGrammar(this.parseAssignmentExpression);
            this.context.allowIn = previousAllowIn;

            this.expect(':');
            const alternate = this.isolateCoverGrammar(this.parseAssignmentExpression);

            expr = this.finalize(this.startNode(startToken), new Node.ConditionalExpression(expr, consequent, alternate));
            this.context.isAssignmentTarget = false;
            this.context.isBindingElement = false;
        }

        return expr;
    }

    // https://tc39.github.io/ecma262/#sec-assignment-operators