basant307/AI_Governance_Project

1"use strict"2    // global key for user preferred registration3var REGISTRATION_KEY = '@@any-promise/REGISTRATION',4    // Prior registration (preferred or detected)5    registered = null6 7/**8 * Registers the given implementation.  An implementation must9 * be registered prior to any call to `require("any-promise")`,10 * typically on application load.11 *12 * If called with no arguments, will return registration in13 * following priority:14 *15 * For Node.js:16 *17 * 1. Previous registration18 * 2. global.Promise if node.js version >= 0.1219 * 3. Auto detected promise based on first sucessful require of20 *    known promise libraries. Note this is a last resort, as the21 *    loaded library is non-deterministic. node.js >= 0.12 will22 *    always use global.Promise over this priority list.23 * 4. Throws error.24 *25 * For Browser:26 *27 * 1. Previous registration28 * 2. window.Promise29 * 3. Throws error.30 *31 * Options:32 *33 * Promise: Desired Promise constructor34 * global: Boolean - Should the registration be cached in a global variable to35 * allow cross dependency/bundle registration?  (default true)36 */37module.exports = function(root, loadImplementation){38  return function register(implementation, opts){39    implementation = implementation || null40    opts = opts || {}41    // global registration unless explicitly  {global: false} in options (default true)42    var registerGlobal = opts.global !== false;43 44    // load any previous global registration45    if(registered === null && registerGlobal){46      registered = root[REGISTRATION_KEY] || null47    }48 49    if(registered !== null50        && implementation !== null51        && registered.implementation !== implementation){52      // Throw error if attempting to redefine implementation53      throw new Error('any-promise already defined as "'+registered.implementation+54        '".  You can only register an implementation before the first '+55        ' call to require("any-promise") and an implementation cannot be changed')56    }57 58    if(registered === null){59      // use provided implementation60      if(implementation !== null && typeof opts.Promise !== 'undefined'){61        registered = {62          Promise: opts.Promise,63          implementation: implementation64        }65      } else {66        // require implementation if implementation is specified but not provided67        registered = loadImplementation(implementation)68      }69 70      if(registerGlobal){71        // register preference globally in case multiple installations72        root[REGISTRATION_KEY] = registered73      }74    }75 76    return registered77  }78}79