function canUsePostMessage()

in www/benchmarks/setImmediate.js [95:112]

• 7 lines of code
• 3 McCabe index (conditional complexity)

    function canUsePostMessage() {
        // The test against `importScripts` prevents this implementation from being installed inside a web worker,
        // where `global.postMessage` means something completely different and can't be used for this purpose.

        if (!global.postMessage || global.importScripts) {
            return false;
        }

        var postMessageIsAsynchronous = true;
        var oldOnMessage = global.onmessage;
        global.onmessage = function () {
            postMessageIsAsynchronous = false;
        };
        global.postMessage("", "*");
        global.onmessage = oldOnMessage;

        return postMessageIsAsynchronous;
    }