63 lines
1.7 KiB
JavaScript
63 lines
1.7 KiB
JavaScript
module.exports = extend;
|
|
|
|
/*
|
|
var obj = {a: 3, b: 5};
|
|
extend(obj, {a: 4, c: 8}); // {a: 4, b: 5, c: 8}
|
|
obj; // {a: 4, b: 5, c: 8}
|
|
|
|
var obj = {a: 3, b: 5};
|
|
extend({}, obj, {a: 4, c: 8}); // {a: 4, b: 5, c: 8}
|
|
obj; // {a: 3, b: 5}
|
|
|
|
var arr = [1, 2, 3];
|
|
var obj = {a: 3, b: 5};
|
|
extend(obj, {c: arr}); // {a: 3, b: 5, c: [1, 2, 3]}
|
|
arr.push(4);
|
|
obj; // {a: 3, b: 5, c: [1, 2, 3, 4]}
|
|
|
|
var arr = [1, 2, 3];
|
|
var obj = {a: 3, b: 5};
|
|
extend(true, obj, {c: arr}); // {a: 3, b: 5, c: [1, 2, 3]}
|
|
arr.push(4);
|
|
obj; // {a: 3, b: 5, c: [1, 2, 3]}
|
|
|
|
extend({a: 4, b: 5}); // {a: 4, b: 5}
|
|
extend({a: 4, b: 5}, 3); {a: 4, b: 5}
|
|
extend({a: 4, b: 5}, true); {a: 4, b: 5}
|
|
extend('hello', {a: 4, b: 5}); // throws
|
|
extend(3, {a: 4, b: 5}); // throws
|
|
*/
|
|
|
|
function extend(/* [deep], obj1, obj2, [objn] */) {
|
|
var args = [].slice.call(arguments);
|
|
var deep = false;
|
|
if (typeof args[0] == 'boolean') {
|
|
deep = args.shift();
|
|
}
|
|
var result = args[0];
|
|
if (!result || (typeof result != 'object' && typeof result != 'function')) {
|
|
throw new Error('extendee must be an object');
|
|
}
|
|
var extenders = args.slice(1);
|
|
var len = extenders.length;
|
|
for (var i = 0; i < len; i++) {
|
|
var extender = extenders[i];
|
|
for (var key in extender) {
|
|
if (extender.hasOwnProperty(key)) {
|
|
var value = extender[key];
|
|
if (deep && isCloneable(value)) {
|
|
var base = Array.isArray(value) ? [] : {};
|
|
result[key] = extend(true, result.hasOwnProperty(key) ? result[key] : base, value);
|
|
} else {
|
|
result[key] = value;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
function isCloneable(obj) {
|
|
return Array.isArray(obj) || {}.toString.call(obj) == '[object Object]';
|
|
}
|