founddrama / a..z

A little JavaScript library for creating string ranges.

a..z

a..z is a tiny, self-contained JavaScript library for generating ranges of letters characters. Give it the start and end characters, and it spits out that range, as an array.

a..z has one exported function: range.

API

range a..z.range(alpha, omega, stepFn)

Produces a range (an Array) starting with the character alpha and ending with omega. Optionally provide stepFn to alter the intervals between the letters in the produced range. If you provide a stepFn, it takes a single argument which is a Number and returns a Number.

Examples

In Node, just require a..z:

var a..z = require('a..z');

Give it a single letter, and get that letter back out:

a..z.range('a');
//=> ['a']

Give it a start an end letter, and you get all the letters in between:

a..z.range('a', 'd');
//=> ['a', 'b', 'c', 'd']

Want the letters reversed? Just give them reversed:

a..z.range('Z', 'W');
//=> ['Z', 'Y', 'X', 'W']

Give code points and get those characters out:

a..z.range(91, 94);
//=> ['[', '\\', ']', '^']

Provide a step function as a third argument to skip letters:

a..z.range('A', 'J', function(c) { return x + 3; });
//=> ['A', 'D', 'G', 'J']

Or get really crazy:

a..z.range('A', 'B', (function() {
  var n = 0;
  
  return function(c) {
    if (n < 1) {
      n += 1;
      return c;
    } else {
      n = 0;
      return c + 1;
    }
  };
}()));
//=> [ 'a', 'a', 'b', 'b' ];

There's also a little .. notation for creating the ranges, if you're into that sort of thing:

a..z.range('a..d');
//=> ['a', 'b', 'c', 'd']
a..z.range('a..<d');
//=> ['a', 'b', 'c']

Tests!

a..z has a bunch of nodeunit tests. You can run them:

npm install && grunt nodeunit:all

(BTW: If you haven't already, you should have Grunt installed globally: npm install -g grunt-cli)

License

a..z is available for use under the MIT software license.