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// 26.1.2 Reflect.construct(target, argumentsList [, newTarget])
var $ = require('./$')
, $export = require('./$.export')
, aFunction = require('./$.a-function')
, anObject = require('./$.an-object')
, isObject = require('./$.is-object')
, bind = Function.bind || require('./$.core').Function.prototype.bind;
// MS Edge supports only 2 arguments
// FF Nightly sets third argument as `new.target`, but does not create `this` from it
$export($export.S + $export.F * require('./$.fails')(function(){
function F(){}
return !(Reflect.construct(function(){}, [], F) instanceof F);
}), 'Reflect', {
construct: function construct(Target, args /*, newTarget*/){
aFunction(Target);
anObject(args);
var newTarget = arguments.length < 3 ? Target : aFunction(arguments[2]);
if(Target == newTarget){
// w/o altered newTarget, optimization for 0-4 arguments
switch(args.length){
case 0: return new Target;
case 1: return new Target(args[0]);
case 2: return new Target(args[0], args[1]);
case 3: return new Target(args[0], args[1], args[2]);
case 4: return new Target(args[0], args[1], args[2], args[3]);
}
// w/o altered newTarget, lot of arguments case
var $args = [null];
$args.push.apply($args, args);
return new (bind.apply(Target, $args));
}
// with altered newTarget, not support built-in constructors
var proto = newTarget.prototype
, instance = $.create(isObject(proto) ? proto : Object.prototype)
, result = Function.apply.call(Target, instance, args);
return isObject(result) ? result : instance;
}
});
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