pxg-collection v0.0.6
WARNING
This module has been deprecated. Please use the latest release of dictionaryjs which now supports all es6 features.
See:
PXG Collection
A Collection (Associative Array like) Class for ES6. Now supporting dot and bracket without a proxy, and generator/yield control flows.
Features
- Stores key/value pairs within a Associative Array like collections.
- Use dot operator and brackets to access keys.
- Remove key using the DELETE operator.
- Iterator to support for..of looping.
- Generator/yield async control flow (via suspend module) support.
- Set and Get methods for accessing keys.
- GetDefault method with default value if value is not found.
- Remove method to remove key from collection.
- Size method to get total key count within collection.
- Built-in forEach and asyncForEach methods for looping.
- Empty and asyncEmpty to remove all entries from collection.
- Has method checking if key is within collection.
Install
Requirements
- ECMAScript 2015 (ES6)
- Node.JS 6.2.2 or later (tested on 6.2.2)
You may find the older version (with less features) but will work with older version of Node.js: dictionaryjs
Proxy Version
A version made with Proxy is also available which will automatically invalidate keys: dictionaryjs-es6
However, do note: node.js (v8/chromium) has a known bug when debugging around Proxy, which is the reason why this new Collection class was made.
Basic Example
Constructor
Where:
- resume - the reference to the suspend library's resume factory
cacheKeys - (default false) - if keys should be cached
Caching keys should only be enabled if you plan to strictly use the set(key,value) method, or if you plan to invalidate() yourself manually.
Accessing and Setting Keys
You may access keys using the get/set methods, but also using the dot operator and brackets.
Standard get/set methods:
Dot operator:
Bracket operators:
You may also use the getDefault(key,defaultValue) method if the key was not found (or is null):
Checking if Key exists
Deleting Keys
To remove a key, you may use the remove(key) method, or the delete operator:
To empty the collection:
Looping through keys
ForEach (Blocking)
AsyncForEach (Non-Blocking)
Using the (for...of) loop:
Each value within the collection can be accessed in a for...of loop. This is blocking.
To loop through each key within the collection you may use the for...in loop. This is blocking.
Getting the Collection Size:
Generator/yield Async control flow using Suspend (recommended)
Using the suspend module you may write async code using the new yield command. Here is an example that will show how you can write async code in a very clean manner:
Other methods
These methods you may not find useful, but are documented in case you do:
- getKeys() - Returns an array of keys
- invalidate() - Invalidates the keys, used if you enable caching
- setResume(resume) - used to set the suspend.resume reference, usually set in the constructor.