promise.js
function GetCapabilitiesExecutor () {
    return function F ( resolve, reject ) {
      var promiseCapability = F['[[Capability]]'];
      if ( Type(promiseCapability['[[Resolve]]']) !== 'undefined' ) {
        throw TypeError();
      }
      if ( Type(promiseCapability['[[Reject]]']) !== 'undefined' ) {
        throw TypeError();
      }
      defineInternal(promiseCapability, '[[Resolve]]', resolve);
      defineInternal(promiseCapability, '[[Reject]]', reject);
    };
  }
function GetCapabilitiesExecutor () {
    return function F ( resolve, reject ) {
      var promiseCapability = F['[[Capability]]'];
      if ( Type(promiseCapability['[[Resolve]]']) !== 'undefined' ) {
        throw TypeError();
      }
      if ( Type(promiseCapability['[[Reject]]']) !== 'undefined' ) {
        throw TypeError();
      }
      defineInternal(promiseCapability, '[[Resolve]]', resolve);
      defineInternal(promiseCapability, '[[Reject]]', reject);
    };
  }
25.4.1.5.2 GetCapabilitiesExecutor Functions