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1var baseCreate = require('./_baseCreate'),
2 isObject = require('./isObject');
3
4/**
5 * Creates a function that produces an instance of `Ctor` regardless of
6 * whether it was invoked as part of a `new` expression or by `call` or `apply`.
7 *
8 * @private
9 * @param {Function} Ctor The constructor to wrap.
10 * @returns {Function} Returns the new wrapped function.
11 */
12function createCtor(Ctor) {
13 return function() {
14 // Use a `switch` statement to work with class constructors. See
15 // http://ecma-international.org/ecma-262/7.0/#sec-ecmascript-function-objects-call-thisargument-argumentslist
16 // for more details.
17 var args = arguments;
18 switch (args.length) {
19 case 0: return new Ctor;
20 case 1: return new Ctor(args[0]);
21 case 2: return new Ctor(args[0], args[1]);
22 case 3: return new Ctor(args[0], args[1], args[2]);
23 case 4: return new Ctor(args[0], args[1], args[2], args[3]);
24 case 5: return new Ctor(args[0], args[1], args[2], args[3], args[4]);
25 case 6: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5]);
26 case 7: return new Ctor(args[0], args[1], args[2], args[3], args[4], args[5], args[6]);
27 }
28 var thisBinding = baseCreate(Ctor.prototype),
29 result = Ctor.apply(thisBinding, args);
30
31 // Mimic the constructor's `return` behavior.
32 // See https://es5.github.io/#x13.2.2 for more details.
33 return isObject(result) ? result : thisBinding;
34 };
35}
36
37module.exports = createCtor;