set-tools

What is it?

set-tools is a prototype extension module for beefing up JavaScript's Set type to include all of your favorite set operations, including difference, union, intersection, issubset, issuperset, and toArray.

What else?

This module is a bit naughty. Normally you are not supposed to extend global JavaScript prototypes. This is because it affects any and all other modules you have loaded. Having said that, these operations are useful and will hopefully be introduced one day as native methods on Set. Assuming no other module is requiring Set to have different implementations of these methods or for some reason requiring them not to be there, then this module won't harm anything.

Installation

npm install set-tools --save

Usage

require('set-tools'); // requiring it supercharges Set prototype automatically.

var s, cmp, results;

/**
 * intersection
 */
s = new Set([1, 3, 5, 7, 9]);
cmp = new Set([2, 3, 8, 9]);
results = s.intersection(cmp); // Set {3, 9}




/**
 * union
 */
s = new Set([1, 3, 5, 7, 9]);
cmp = new Set([2, 3, 8, 9]);
results = s.union(cmp); // Set {2, 3, 8, 9, 1, 5, 7}




/**
 * difference
 */
s = new Set([1, 3, 5, 7, 9]);
cmp = new Set([2, 3, 8, 9]);
results = s.difference(cmp); // Set {1, 5, 7}




/**
 * issubset
 */
s = new Set([1, 3, 5, 7, 9]);
cmp = new Set([3, 5]);
results = s.issuperset(cmp); // true

s = new Set([1, 3, 5, 7, 9]);
cmp = new Set([3, 8]);
results = s.issuperset(cmp); // false




/**
 * issuperset
 */
s = new Set([11, 15, 18, 20]);
cmp = new Set([11, 15, 18, 20, 25, 89, 100]);
results = s.issubset(cmp); // true

s = new Set([11, 15, 18, 57, 62]);
cmp = new Set([11, 15, 18, 20, 25, 89, 100]);
results = s.issubset(cmp); // false

Contributing

Pull requests are much appreciated and accepted.

License

Released under the MIT License