time-to-botec

Benchmark sampling in different programming languages
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_createPartial.js (1382B)

      1 var apply = require('./_apply'),
      2     createCtor = require('./_createCtor'),
      3     root = require('./_root');
      4 
      5 /** Used to compose bitmasks for function metadata. */
      6 var WRAP_BIND_FLAG = 1;
      7 
      8 /**
      9  * Creates a function that wraps `func` to invoke it with the `this` binding
     10  * of `thisArg` and `partials` prepended to the arguments it receives.
     11  *
     12  * @private
     13  * @param {Function} func The function to wrap.
     14  * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
     15  * @param {*} thisArg The `this` binding of `func`.
     16  * @param {Array} partials The arguments to prepend to those provided to
     17  *  the new function.
     18  * @returns {Function} Returns the new wrapped function.
     19  */
     20 function createPartial(func, bitmask, thisArg, partials) {
     21   var isBind = bitmask & WRAP_BIND_FLAG,
     22       Ctor = createCtor(func);
     23 
     24   function wrapper() {
     25     var argsIndex = -1,
     26         argsLength = arguments.length,
     27         leftIndex = -1,
     28         leftLength = partials.length,
     29         args = Array(leftLength + argsLength),
     30         fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
     31 
     32     while (++leftIndex < leftLength) {
     33       args[leftIndex] = partials[leftIndex];
     34     }
     35     while (argsLength--) {
     36       args[leftIndex++] = arguments[++argsIndex];
     37     }
     38     return apply(fn, isBind ? thisArg : this, args);
     39   }
     40   return wrapper;
     41 }
     42 
     43 module.exports = createPartial;