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var apply = require('./_apply'),    createCtor = require('./_createCtor'),    root = require('./_root');
/** Used to compose bitmasks for function metadata. */var WRAP_BIND_FLAG = 1;
/** * Creates a function that wraps `func` to invoke it with the `this` binding * of `thisArg` and `partials` prepended to the arguments it receives. * * @private * @param {Function} func The function to wrap. * @param {number} bitmask The bitmask flags. See `createWrap` for more details. * @param {*} thisArg The `this` binding of `func`. * @param {Array} partials The arguments to prepend to those provided to *  the new function. * @returns {Function} Returns the new wrapped function. */function createPartial(func, bitmask, thisArg, partials) {  var isBind = bitmask & WRAP_BIND_FLAG,      Ctor = createCtor(func);
  function wrapper() {    var argsIndex = -1,        argsLength = arguments.length,        leftIndex = -1,        leftLength = partials.length,        args = Array(leftLength + argsLength),        fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
    while (++leftIndex < leftLength) {      args[leftIndex] = partials[leftIndex];    }    while (argsLength--) {      args[leftIndex++] = arguments[++argsIndex];    }    return apply(fn, isBind ? thisArg : this, args);  }  return wrapper;}
module.exports = createPartial;