jussi-kalliokoski/setImmediate.js

## setImmediate.js
(function (global, prefixes, timeouts, id, i) {

if (typeof process !== 'undefined' && process && process.nextTick) {
	global.setImmediate = function (callback, args) {
		var i = id;

		timeouts[id] = {
			c: callback,
			a: args || [],
		};

		process.nextTick(function () {
			var t = timeouts[i];
			if (t) {
				t.c.apply(global, t.a);
				delete timeouts[i];
			}
		});
		return id++;
	};

	global.clearImmediate = function (id) {
		timeouts[id] && delete timeouts[id];
	};
	return;
}

for (i=0; !global.setImmediate && i<prefixes.length; i++) {
	global.setImmediate	= global[prefixes[i] + 'SetImmediate'];
	global.clearImmediate	= global[prefixes[i] + 'ClearImmediate'];
}

if (!global.setImmediate && global.postMessage && global.addEventListener) {
	global.addEventListener('message', function (e) {
		if (!e.data || e.source !== global  || !e.data.setImmediate) return;

		e.preventDefault && e.preventDefault();
		e.stopPropagation && e.stopPropagation();

		var t = timeouts[e.data.setImmediate];

		if (t) {
			t.c.apply(global, t.a);
			delete timeouts[e.data.setImmediate];
		}
	}, true);

	global.setImmediate = function (callback, args) {
		timeouts[id] = {
			c: callback,
			a: args || [],
		};
		global.postMessage({
			setImmediate: id,
		}, '*');
		return id++;
	};

	global.clearImmediate = function (id) {
		timeouts[id] && delete timeouts[id];
	};
	return;
}

if (!global.setImmediate && global.setInterval) {
	global.setImmediate = function (callback, args) {
		return global.setTimeout(callback, 0, args);
	};
	global.clearImmediate = global.clearTimeout;
	return;
}

}(typeof global !== 'undefined' && global ? global : this, ['webkit', 'moz', 'ms', 'o'], {}, +new Date));

## test.html
<!DOCTYPE html>
<html>
<head>
</head>
<body>
	<div id="r"></div>
	<script src="setImmediate.js"></script>
	<script>
function printResult () {
	var e = document.createElement('div');
	e.appendChild(document.createTextNode([].slice.call(arguments).join(' ')));
	document.getElementById('r').appendChild(e);
}

var start = +new Date;

setImmediate(function (s) {
	printResult('It worked and took', +new Date - s, 'milliseconds.');
}, [start]);

var canceling = setImmediate(function () {
	printResult('ERROR: this should not have appeared.');
});

printResult('Attempting to cancel immediate with id:', canceling);

clearImmediate(canceling);
	</script>
</body>
</html>

## test.js
// Test for node.js and jsshell (unsupported because it doesn't even have setTimeout)

typeof require === 'undefined' ? load('setImmediate.js') : require('./setImmediate.js');

function printResult () {
	var msg = [].slice.call(arguments).join(' ');

	typeof print === 'undefined' ? console.log(msg) : print(msg);
}

var start = +new Date;

setImmediate(function (s) {
	printResult('It worked and took', +new Date - s, 'milliseconds.');
}, [start]);

var canceling = setImmediate(function () {
	printResult('ERROR: this should not have appeared.');
});

printResult('Attempting to cancel immediate with id:', canceling);

clearImmediate(canceling);
	(function (global, prefixes, timeouts, id, i) {

	if (typeof process !== 'undefined' && process && process.nextTick) {
	global.setImmediate = function (callback, args) {
	var i = id;

	timeouts[id] = {
	c: callback,
	a: args \|\| [],
	};

	process.nextTick(function () {
	var t = timeouts[i];
	if (t) {
	t.c.apply(global, t.a);
	delete timeouts[i];
	}
	});
	return id++;
	};

	global.clearImmediate = function (id) {
	timeouts[id] && delete timeouts[id];
	};
	return;
	}

	for (i=0; !global.setImmediate && i<prefixes.length; i++) {
	global.setImmediate = global[prefixes[i] + 'SetImmediate'];
	global.clearImmediate = global[prefixes[i] + 'ClearImmediate'];
	}

	if (!global.setImmediate && global.postMessage && global.addEventListener) {
	global.addEventListener('message', function (e) {
	if (!e.data \|\| e.source !== global \|\| !e.data.setImmediate) return;

	e.preventDefault && e.preventDefault();
	e.stopPropagation && e.stopPropagation();

	var t = timeouts[e.data.setImmediate];

	if (t) {
	t.c.apply(global, t.a);
	delete timeouts[e.data.setImmediate];
	}
	}, true);

	global.setImmediate = function (callback, args) {
	timeouts[id] = {
	c: callback,
	a: args \|\| [],
	};
	global.postMessage({
	setImmediate: id,
	}, '*');
	return id++;
	};

	global.clearImmediate = function (id) {
	timeouts[id] && delete timeouts[id];
	};
	return;
	}

	if (!global.setImmediate && global.setInterval) {
	global.setImmediate = function (callback, args) {
	return global.setTimeout(callback, 0, args);
	};
	global.clearImmediate = global.clearTimeout;
	return;
	}

	}(typeof global !== 'undefined' && global ? global : this, ['webkit', 'moz', 'ms', 'o'], {}, +new Date));
	<!DOCTYPE html>
	<html>
	<head>
	</head>
	<body>
	<div id="r"></div>
	<script src="setImmediate.js"></script>
	<script>
	function printResult () {
	var e = document.createElement('div');
	e.appendChild(document.createTextNode([].slice.call(arguments).join(' ')));
	document.getElementById('r').appendChild(e);
	}

	var start = +new Date;

	setImmediate(function (s) {
	printResult('It worked and took', +new Date - s, 'milliseconds.');
	}, [start]);

	var canceling = setImmediate(function () {
	printResult('ERROR: this should not have appeared.');
	});

	printResult('Attempting to cancel immediate with id:', canceling);

	clearImmediate(canceling);
	</script>
	</body>
	</html>
	// Test for node.js and jsshell (unsupported because it doesn't even have setTimeout)

	typeof require === 'undefined' ? load('setImmediate.js') : require('./setImmediate.js');

	function printResult () {
	var msg = [].slice.call(arguments).join(' ');

	typeof print === 'undefined' ? console.log(msg) : print(msg);
	}

	var start = +new Date;

	setImmediate(function (s) {
	printResult('It worked and took', +new Date - s, 'milliseconds.');
	}, [start]);

	var canceling = setImmediate(function () {
	printResult('ERROR: this should not have appeared.');
	});

	printResult('Attempting to cancel immediate with id:', canceling);

	clearImmediate(canceling);