fill-range NPM version Build Status

Fill in a range of numbers or letters, optionally passing an increment or multiplier to use.

Install with npm

npm i fill-range --save

(Table of contents generated by [verb])

Usage

var range = require('fill-range');

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

Params

range(start, stop, step, options, fn);

Examples

range(1, 3)
//=> ['1', '2', '3']

range('1', '3')
//=> ['1', '2', '3']

range('0', '-5')
//=> [ '0', '-1', '-2', '-3', '-4', '-5' ]

range(-9, 9, 3)
//=> [ '-9', '-6', '-3', '0', '3', '6', '9' ])

range('-1', '-10', '-2')
//=> [ '-1', '-3', '-5', '-7', '-9' ]

range('1', '10', '2')
//=> [ '1', '3', '5', '7', '9' ]

range('a', 'e')
//=> ['a', 'b', 'c', 'd', 'e']

range('a', 'e', 2)
//=> ['a', 'c', 'e']

range('A', 'E', 2)
//=> ['A', 'C', 'E']

Invalid ranges

When an invalid range is passed, null is returned.

range('1.1', '2');
//=> null

range('a', '2');
//=> null

range(1, 10, 'foo');
//=> null

If you want errors to be throw, pass silent: false on the options:

Custom function

Optionally pass a custom function as the third or fourth argument:

range('a', 'e', function (val, isNumber, pad, i) {
  if (!isNumber) {
    return String.fromCharCode(val) + i;
  }
  return val;
});
//=> ['a0', 'b1', 'c2', 'd3', 'e4']

Special characters

A special character may be passed as the third arg instead of a step increment. These characters can be pretty useful for brace expansion, creating file paths, test fixtures and similar use case.

range('a', 'z', SPECIAL_CHARACTER_HERE);

Supported characters

plus

Character: (+)

Repeat the first argument the number of times passed on the second argument.

Examples:

range('a', 3, '+');
//=> ['a', 'a', 'a']

range('abc', 2, '+');
//=> ['abc', 'abc']

pipe and tilde

Characters: (| and ~)

Creates a regex-capable string (either a logical or or a character class) from the expanded arguments.

Examples:

range('a', 'c', '|');
//=> ['(a|b|c)'

range('a', 'c', '~');
//=> ['[a-c]'

range('a', 'z', '|5');
//=> ['(a|f|k|p|u|z)'

Automatic separator correction

To avoid this error:

Range out of order in character class

Fill-range detects invalid sequences and uses the correct syntax. For example:

invalid (regex)

If you pass these:

range('a', 'z', '~5');
// which would result in this
//=> ['[a-f-k-p-u-z]']

range('10', '20', '~');
// which would result in this
//=> ['[10-20]']

valid (regex)

fill-range corrects them to this:

range('a', 'z', '~5');
//=> ['(a|f|k|p|u|z)'

range('10', '20', '~');
//=> ['(10-20)'

angle bracket

Character: (>)

Joins all values in the returned array to a single value.

Examples:

range('a', 'e', '>');
//=> ['abcde']

range('5', '8', '>');
//=> ['5678']

range('2', '20', '2>');
//=> ['2468101214161820']

question mark

Character: (?)

Uses randomatic to generate randomized alpha, numeric, or alpha-numeric patterns based on the provided arguments.

Examples:

(actual results would obviously be randomized)

Generate a 5-character, uppercase, alphabetical string:

range('A', 5, '?');
//=> ['NSHAK']

Generate a 5-digit random number:

range('0', 5, '?');
//=> ['36583']

Generate a 10-character alpha-numeric string:

range('A0', 10, '?');
//=> ['5YJD60VQNN']

See the randomatic repo for all available options and or to create issues or feature requests related to randomization.

Other useful libs

Running tests

Install dev dependencies:

npm i -d && npm test

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue

Author

Jon Schlinkert

License

Copyright (c) 2014-2015 Jon Schlinkert
Released under the MIT license


This file was generated by verb-cli on April 07, 2015.