README
¶
An EventEmitter for Go
This package is a modification of eventemitter package by CHH. Modifications are:
- Ability to remove select event listeners.
Install
With go get:
% go get github.com/ishbir/eventemitter
Usage
For more information please also see the Package Docs.
A new EventEmitter is created by the New function.
import "github.com/ishbir/eventemitter"
func main() {
emitter := eventemitter.New()
}
A listener is of type func (event *ee.Event)
Listeners can be bound to event names with the On method:
emitter.On("foo", func(name string) {
fmt.Printf("Hello World %s", name)
}, 1)
An event can be triggered by calling the Emit method:
<- emitter.Emit("foo", "John")
When Emit is called, each registered listener is called in
its own Goroutine. They all share a common channel, which is
returned by the Emit function.
var c chan interface{}
c = emitter.Emit("foo", "John")
This channel can be used to wait until all listeners have finished, by using the
<- operator without variable:
<- emitter.Emit("foo", "John")
Each listener yields a reference to eventemitter.Response on the
channel once it has finished:
c := emitter.Emit("foo", "John")
for resp := <- c {
// Do something
}
Embedding
EventEmitters can also be embedded in other types. When embedding you've
to call the Init function on the EventEmitter, so the memory is
correctly allocated:
type Server struct {
eventemitter.EventEmitter
}
func NewServer() *Server {
s := new(Server)
// Allocates the EventEmitter's memory.
s.EventEmitter.Init()
// All functions of the EventEmitter are available:
s.On("foo", func() {
}, 2)
}
License
EventEmitter is distributed under the Terms of the MIT License. See
the bundled file LICENSE.txt for more information.
Documentation
¶
Index ¶
- type EventEmitter
- func (self *EventEmitter) AddListener(event string, listener interface{}, id interface{})
- func (self *EventEmitter) Emit(event string, argv ...interface{}) <-chan *Response
- func (self *EventEmitter) Init()
- func (self *EventEmitter) Listeners(event string) []Listener
- func (self *EventEmitter) On(event string, listener interface{}, id interface{})
- func (self *EventEmitter) RemoveListener(event string, id interface{})
- func (self *EventEmitter) RemoveListeners(event string)
- type Listener
- type Response
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type EventEmitter ¶
type EventEmitter struct {
// contains filtered or unexported fields
}
Example ¶
// Construct a new EventEmitter instance
emitter := New()
emitter.On("hello", func() {
fmt.Println("Hello World")
}, 1)
emitter.On("hello", func() {
fmt.Println("Hello Hello World")
}, 2)
// Wait until all handlers have finished
<-emitter.Emit("hello")
Output: Hello World Hello Hello World
func New ¶
func New() *EventEmitter
func (*EventEmitter) AddListener ¶
func (self *EventEmitter) AddListener(event string, listener interface{}, id interface{})
AddListener adds an event listener on the given event name. id is used to keep track of different listeners and distinguish one from the other. If a listener with a duplicate id is added, the second one is ignored.
func (*EventEmitter) Emit ¶
func (self *EventEmitter) Emit(event string, argv ...interface{}) <-chan *Response
Emits the given event. Puts all arguments following the event name into the Event's `Argv` member. Returns a channel if listeners were called, nil otherwise.
Example ¶
emitter := New()
emitter.On("hello", func(name string) {
fmt.Printf("Hello World %s\n", name)
}, 3)
<-emitter.Emit("hello", "John")
Output: Hello World John
func (*EventEmitter) Init ¶
func (self *EventEmitter) Init()
Allocates the EventEmitters memory. Has to be called when embedding an EventEmitter in another Type.
Example ¶
package main
type SampleServer struct {
EventEmitter
}
func NewServer() *Server {
s := new(Server)
// Initialize Maps
s.EventEmitter.Init()
return s
}
func main() {
s := NewServer()
// Do something
s.Emit("connect" /*, conn */)
}
Output:
func (*EventEmitter) Listeners ¶
func (self *EventEmitter) Listeners(event string) []Listener
func (*EventEmitter) On ¶
func (self *EventEmitter) On(event string, listener interface{}, id interface{})
Alias to AddListener.
func (*EventEmitter) RemoveListener ¶
func (self *EventEmitter) RemoveListener(event string, id interface{})
RemoveListener removes the listener listening to `event' with the specified id.
func (*EventEmitter) RemoveListeners ¶
func (self *EventEmitter) RemoveListeners(event string)
RemoveListeners removes all listeners from the given event.
Source Files