This module implements EventSource, which lets you register event handlers and then emit events.

Example:

import events
var
  es = newEventSource[string]()
  messages: seq[string]
  count: int
es.handle(msg):
  messages.add(msg)
es.handle:
  inc(count)
es.emit("foo")
es.emit("bar")
doAssert messages == @["foo", "bar"]
doAssert count == 2

Types

EventSource[T] = object listeners: seq[proc (message: T): void]

Procs

proc `$`(ev: EventSource): string
proc `$`(ev: ref EventSource): string
proc addListener[T](es: var EventSource[T]; listener: proc (message: T): void): Add a proc to handle events. Proc will be called once for each event emit. See the handle template for a nicer syntax.
proc emit[T](es: EventSource[T]; message: T) {....gcsafe.}: Emit an event to all event listeners
proc newEventSource[T](): EventSource[T]
proc removeListener[T](es: var EventSource[T]; listener: proc (message: T): void): Remove a proc from receiving any more events.

Templates

template handle[T](es: EventSource[T]; fnbody: untyped): untyped: Convient syntax for when you don't care about the event's message
Example:

var es = newEventSource[string]() es.handle: echo "Got a message" es.emit("some string")
template handle[T](es: EventSource[T]; varname: untyped; fnbody: untyped): untyped: Convient syntax for addListener
Example:

var es = newEventSource[string]() es.handle(thestring): echo "Got thestring: " & thestring es.emit("some string")