wmap

Map string keys to value with the added ability to specify observer functions for multiple keys.

Usage

Install:

$ npm install wmap

Create:

var wmap = require('wmap');
var myMap = wmap();

Set some keys:

myMap.set('foo', 10);
myMap.set('bar', 15);

Watch a bunch of keys for changes:

var unsubscribe = myMap.watch(['foo', 'bar', 'baz'], function(key, oldValue, newValue) {
    // ...
});

Cancel the subscription:

unsubscribe();

API

map.get(key)

Return element associated with key, or undefined if no mapping exists.

map.set(key, value)

Associate value with key, triggering any observers set on key.

map.remove(key)

Remove mapping for key, triggering any observers set on key.

map.watch(keys, cb)

Watch the given array of keys for changes, invoking the supplied callback function whenever mappings for the supplied keys are created, updated or removed. The callback receives 3 arguments: key, previous value and new value. map.watch() returns a function that can be called to cancel the subscription.