Method bind

container.go:44–76

bind maps an abstraction to concrete and instantiates if it is a singleton binding.

(resolver interface{}, name string, isSingleton bool, isLazy bool)

// bind maps an abstraction to concrete and instantiates if it is a singleton binding.
func (c Container) bind(resolver interface{}, name string, isSingleton bool, isLazy bool) error {
	reflectedResolver := reflect.TypeOf(resolver)
	if reflectedResolver.Kind() != reflect.Func {
		return errors.New("container: the resolver must be a function")
	}

	if reflectedResolver.NumOut() > 0 {
		if _, exist := c[reflectedResolver.Out(0)]; !exist {
			c[reflectedResolver.Out(0)] = make(map[string]*binding)
		}
	}

	if err := c.validateResolverFunction(reflectedResolver); err != nil {
		return err
	}

	var concrete interface{}
	if !isLazy {
		var err error
		concrete, err = c.invoke(resolver)
		if err != nil {
			return err
		}
	}

	if isSingleton {
		c[reflectedResolver.Out(0)][name] = &binding{resolver: resolver, concrete: concrete, isSingleton: isSingleton}
	} else {
		c[reflectedResolver.Out(0)][name] = &binding{resolver: resolver, isSingleton: isSingleton}
	}

	return nil
}

func (c Container) validateResolverFunction(funcType reflect.Type) error {
	retCount := funcType.NumOut()