lua-notifier

event notification module.

---

Dependencies

• halo: https://github.com/mah0x211/lua-halo
• util: https://github.com/mah0x211/lua-util

Installation

luarocks install notifier --from=http://mah0x211.github.io/rocks/

Create new notifier object

notifier = Notifier.new()

Returns

1. notifier:table: an instance of notifier.

Methods

Register an event notification observer

notifier = notifier:on( name:string, callback:function [, ctx:any [, count:uint] ] )

Parameters

• name:string: event name.
• callback:function: callback function.
• ctx:any: any context value that passing to first argument of callback function on invocation. (default: nil)
• count:uint: number of notification. if notification count reached to this value, an observer will be removed automatically. (default: 0)

Returns

1. notifier:table: an instance of notifier.

Get a number of notification observers

nobs = notifier:getnobs( name:string )

Parameters

• name:string: event name.

Returns

1. nobs:uint: number of notification observers

Unregister an event notification observer

notifier = notifier:off( name:string, callback:function )

unregister an event notification observer.

Parameters

• name:string: event name.
• callback:function: callback function.

Returns

1. notifier:table: an instance of notifier.

Notify event to event observers.

notified, removed = notifier:notify( name:string [, ...] )

Parameters

• name:string: event name.
• ...: passed arguments of observers.

Returns

1. notified:number: number of notified observer.
2. removed:number: number of removed observer.

Usage

local Notifier = require('notifier');
local notifier = Notifier.new();

local function cbHello( ctx, ... )
    print( ctx, ... );
end

local function cbWorld( ctx, ... )
    print( ctx, ... );
end

local notified, removed;

-- register
notifier
:on( 'hello', cbHello, 'hello context' )
:on( 'world', cbWorld, 'world context', 1 );

-- notify
notified, removed = notifier:notify('hello');
print( notified, removed );

-- notify with arguments
notified, removed = notifier:notify('world', 'a', 'b', 1, 2 );
print( notified, removed );

-- unregister
notifier:off( 'hello', cbHello );