SplitStringByCharacterGroups

Splits a string by character groups that you define. Useful for custom regex manipulation

Helps you split:

'BEAGG#AbB' into [ 'B', 'E', 'A', 'G', 'G#', 'Ab', 'B' ]

'daʊnloʊd' into [ 'd', 'aʊ', 'n', 'l', 'oʊ', 'd' ]

Installation

$ npm i splitstringbycharactergroups

Usage

load the module

const split = require('splitstringbycharactergroups');

call splitStringByCharacterGroups

const input = 'abcd';
const characterGroups = ['bc','a','d'];
const result = split.splitStringByCharacterGroups(input, characterGroups)
// result should be [ 'a', 'bc', 'd' ]

splitStringByCharacterGroups method takes 4 arguments:

1. the input
2. characterGroups, an ordered array of character groups. will usually want longest first.
3. [optional/boolean] ignoreExtraneousCharacters? defaults to true/ignore. set false to return unidentified chars as undefined. see examples.
4. [optional/boolean] splitExtraneousCharacters?. defaults to false/doesn't split. set to true to split unidentified substrings into individual elements of single char length. see examples.

call sortCharacterGroups on an array to return array sorted by character length and reversed alphabetically

const character_groups = ['A','B','C','D','E','F','G','Ab','Bb','Cb','Db','Eb','Fb','Gb','A#','B#','C#','D#','E#','F#','G#'];
const sorted = split.sortCharacterGroups(character_groups);
//sorted should be ['Gb','G#','Fb','F#','Eb','E#','Db','D#','Cb','C#','Bb','B#','Ab','A#','G','F','E','D','C','B','A']

Examples

Get string with musical pitches split into correct groupings

const split = require('SplitStringByCharacterGroups')
const character_groups = ['A','B','C','D','E','F','G','Ab','Bb','Cb','Db','Eb','Fb','Gb','A#','B#','C#','D#','E#','F#','G#'];
const sorted = split.sortCharacterGroups(character_groups);

const input = 'BEAGG#AbB';
const result = split.splitStringByCharacterGroups(input,sorted);
//result should be ['B', 'E', 'A', 'G', 'G#', 'Ab', 'B' ], what we want

//without sorting:
const split_array = split.splitStringByCharacterGroups('BEAGG#AbB',character_groups);
//character groups are not in right order so returns [ 'B', 'E', 'A', 'G', 'G#', 'A', 'b', 'B' ]

optional arguments

Works with unidentified characters:

const split_array = split.splitStringByCharacterGroups('BEAzzzqurGG#Abvv44B', sorted);
// [ 'B', 'E', 'A', 'zzzqur', 'G', 'G#', 'Ab', 'vv44', 'B' ];

Set ignoreExtraneousCharacters param to false to return unidentified characters as undefined:

const split_array = split.splitStringByCharacterGroups('BEAzzzqurGG#Abvv44B', sorted, false);
// [ 'B', 'E', 'A', undefined, 'G', 'G#', 'Ab', undefined, 'B' ]

Set both ignoreExtraneousCharacters and splitExtraneousCharacters params to true to split unidentified substrings into individual single-char-length elements.

const character_groups = ['eɪ','aɪ','aʊ','oʊ','ɔɪ'];
const split_array = s.splitStringByCharacterGroups('daʊnloʊd',character_groups,true,true)
// returns [ 'd', 'aʊ', 'n', 'l', 'oʊ', 'd' ]

Support

ES6+ Node 6+

To do

• Optimize for huge strings/character sets
• Ambiguous cases
• Option to split unidentified substrings into individual elements