Function isUpdateExpression

test/fixtures/snapshot/typescript.js:35016–35039

* Check if the current token can possibly be an ES7 increment expression. * * ES7 UpdateExpression: * LeftHandSideExpression[?Yield] * LeftHandSideExpression[?Yield][no LineTerminator here]++ * LeftHandSideExpression[?Yield][no LineTerminat

()

         *      --LeftHandSideExpression[?Yield]
         */
        function isUpdateExpression() {
            // This function is called inside parseUnaryExpression to decide
            // whether to call parseSimpleUnaryExpression or call parseUpdateExpression directly
            switch (token()) {
                case 39 /* SyntaxKind.PlusToken */:
                case 40 /* SyntaxKind.MinusToken */:
                case 54 /* SyntaxKind.TildeToken */:
                case 53 /* SyntaxKind.ExclamationToken */:
                case 89 /* SyntaxKind.DeleteKeyword */:
                case 112 /* SyntaxKind.TypeOfKeyword */:
                case 114 /* SyntaxKind.VoidKeyword */:
                case 132 /* SyntaxKind.AwaitKeyword */:
                    return false;
                case 29 /* SyntaxKind.LessThanToken */:
                    // If we are not in JSX context, we are parsing TypeAssertion which is an UnaryExpression
                    if (languageVariant !== 1 /* LanguageVariant.JSX */) {
                        return false;
                    }
                // We are in JSX context and the token is part of JSXElement.
                // falls through
                default:
                    return true;
            }
        }
        /**
         * Parse ES7 UpdateExpression. UpdateExpression is used instead of ES6's PostFixExpression.
         *