[Javascript] Closure

Closure

내부함수

Example

function celebrityIDCreator(theCelebrities) {
	var i;
	var uniqueID = 100;
	for (i = 0; i < theCelebrities.length; i++) {
		theCelebrities[i]["id"] = function() {
			return uniqueID + i;
		}
	}
	return theCelebrities;
}
var actionCelebs = [{name:"Stallone", id:0}, {name:"Cruise", id:0}, {name:"Willis", id:0}];
var createIdForActionCelebs = celebrityIDCreator(actionCelebs);

var stalloneID = createIdForActionCelebs[0];
console.log(stalloneID.id());
var cruiseID = createIdForActionCelebs[1];
console.log(cruiseID.id());
var willisID = createIdForActionCelebs[2];
console.log(willisID.id());

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function celebrityIDCreator(theCelebrities) {
	var i;
	var uniqueID = 100;
	for (i = 0; i < theCelebrities.length; i++) {
		theCelebrities[i]["id"] = function(j) {
			return function() {
				return uniqueID + j;
			}()
		}(i);
	}
	return theCelebrities;
}
var actionCelebs = [{name:"Stallone", id:0}, {name:"Cruise", id:0}, {name:"Willis", id:0}];
var createIdForActionCelebs = celebrityIDCreator(actionCelebs);

var stalloneID = createIdForActionCelebs[0];
console.log(stalloneID.id);
var cruiseID = createIdForActionCelebs[1];
console.log(cruiseID.id);
var willisID = createIdForActionCelebs[2];
console.log(willisID.id);

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References

1. http://chanlee.github.io/2013/12/10/understand-javascript-closure/