p.location-badge.
  exported from <a href='../di'>angular2/di</a>
  defined in <a href="https://github.com/angular/angular/tree/2.0.0-alpha.34/modules/angular2/src/di/binding.ts#L258-L371">angular2/src/di/binding.ts (line 258)</a>

:markdown
  Helper class for the <a href='bind-function.html'><code>bind</code></a> function.
  
  
.l-main-section
  h2 Members
  .l-sub-section
    h3 constructor

    
    pre.prettyprint
      code.
        constructor(token: any)
    
    :markdown
      
      




  .l-sub-section
    h3 token

    
    :markdown
      
      





  .l-sub-section
    h3 toClass

    
    pre.prettyprint
      code.
        toClass(type: Type)
    
    :markdown
      Binds an interface to an implementation / subclass.
      
      
      
      Because `toAlias` and `toClass` are often confused, the example contains both use cases for
      easy comparison.
      
      ```javascript
      
      class Vehicle {}
      
      class Car extends Vehicle {}
      
      var injectorClass = Injector.resolveAndCreate([
        Car,
        bind(Vehicle).toClass(Car)
      ]);
      var injectorAlias = Injector.resolveAndCreate([
        Car,
        bind(Vehicle).toAlias(Car)
      ]);
      
      expect(injectorClass.get(Vehicle)).not.toBe(injectorClass.get(Car));
      expect(injectorClass.get(Vehicle) instanceof Car).toBe(true);
      
      expect(injectorAlias.get(Vehicle)).toBe(injectorAlias.get(Car));
      expect(injectorAlias.get(Vehicle) instanceof Car).toBe(true);
      ```
      
      





  .l-sub-section
    h3 toValue

    
    pre.prettyprint
      code.
        toValue(value: any)
    
    :markdown
      Binds a key to a value.
      
      
      
      ```javascript
      var injector = Injector.resolveAndCreate([
        bind(String).toValue('Hello')
      ]);
      
      expect(injector.get(String)).toEqual('Hello');
      ```
      
      





  .l-sub-section
    h3 toAlias

    
    pre.prettyprint
      code.
        toAlias(aliasToken: /*Type*/ any)
    
    :markdown
      Binds a key to the alias for an existing key.
      
      An alias means that we will return the same instance as if the alias token was used. (This is
      in contrast to `toClass` where a separate instance of `toClass` will be returned.)
      
      
      
      Becuse `toAlias` and `toClass` are often confused, the example contains both use cases for easy
      comparison.
      
      ```javascript
      
      class Vehicle {}
      
      class Car extends Vehicle {}
      
      var injectorAlias = Injector.resolveAndCreate([
        Car,
        bind(Vehicle).toAlias(Car)
      ]);
      var injectorClass = Injector.resolveAndCreate([
        Car,
        bind(Vehicle).toClass(Car)
      ]);
      
      expect(injectorAlias.get(Vehicle)).toBe(injectorAlias.get(Car));
      expect(injectorAlias.get(Vehicle) instanceof Car).toBe(true);
      
      expect(injectorClass.get(Vehicle)).not.toBe(injectorClass.get(Car));
      expect(injectorClass.get(Vehicle) instanceof Car).toBe(true);
      ```
      
      





  .l-sub-section
    h3 toFactory

    
    pre.prettyprint
      code.
        toFactory(factoryFunction: Function, dependencies?: List&lt;any&gt;)
    
    :markdown
      Binds a key to a function which computes the value.
      
      
      
      ```javascript
      var injector = Injector.resolveAndCreate([
        bind(Number).toFactory(() => { return 1+2; }),
        bind(String).toFactory((v) => { return "Value: " + v; }, [Number])
      ]);
      
      expect(injector.get(Number)).toEqual(3);
      expect(injector.get(String)).toEqual('Value: 3');
      ```