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'use strict';
var toPosInt = require('../number/to-pos-integer')
, test = function (a, b) {}, desc, defineProperty
, generate, mixin;
try {
Object.defineProperty(test, 'length', { configurable: true, writable: false,
enumerable: false, value: 1 });
} catch (ignore) {}
if (test.length === 1) {
// ES6
desc = { configurable: true, writable: false, enumerable: false };
defineProperty = Object.defineProperty;
module.exports = function (fn, length) {
length = toPosInt(length);
if (fn.length === length) return fn;
desc.value = length;
return defineProperty(fn, 'length', desc);
};
} else {
mixin = require('../object/mixin');
generate = (function () {
var cache = [];
return function (l) {
var args, i = 0;
if (cache[l]) return cache[l];
args = [];
while (l--) args.push('a' + (++i).toString(36));
return new Function('fn', 'return function (' + args.join(', ') +
') { return fn.apply(this, arguments); };');
};
}());
module.exports = function (src, length) {
var target;
length = toPosInt(length);
if (src.length === length) return src;
target = generate(length)(src);
try { mixin(target, src); } catch (ignore) {}
return target;
};
}
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