Regular Expression Utility

Usage

CommonJS

const {toPattern} = require('@taufik-nurrohman/pattern');

console.log(toPattern('[a-z]+'));

ECMAScript

import {toPattern} from '@taufik-nurrohman/pattern';

console.log(toPattern('[a-z]+'));

Methods

esc(pattern, extra = "")

Escape regular expression characters in string except \.

escChar(pattern, extra = "")

Escape regular expression characters for character class only. E.g. ^, [, ], and -.

extractInner(content, start, end, opt = "")

Extract nesting constructs in a string.

console.log(extractInner('a(b(c))d(e)f((g)h)', '\\(', '\\)'));

[
    ['b(c)', [
        ['c', [], 2, 3]
    ], 2, 6],
    ['e', [], 9, 10],
    ['(g)h', [
        ['g', [], 1, 2]
    ], 13, 17]
]

extractTokens(content, tokens, defaultTokenName = 0)

console.log(extractTokens('This is an <a href="https://example.com">active link</a> and an <a>empty link</a>.', [
    ['(<)([\\w:-]+)(\\s[^>]*?)?(>)', ['tag', 'p', 'name', [
        ['"[^"]+"', 'value'],
        ['=', 'p'],
        ['[\\w:-]+', 'key']
    ], 'p']],
    ['(<)(/)([\\w:-]+)(>)', ['tag', 'p', 'p', 'name', 'p']]
]));

[
    [['This is an '], [0]],
    [['<a href="https://example.com">', '<', 'a', ' href="https://example.com"', '>'], ['tag', 'p', 'name', [
        [[' '], [0]],
        [['href'], ['key']],
        [['='], ["p"]],
        [['"https://example.com"'], ['value']]
    ], 'p']],
    [['active link'], [0]],
    [['</a>', '<', '/', 'a', '>'], ['tag', 'p', 'p', 'name', 'p']],
    [[' and an '], [0]],
    [['<a>', '<', 'a', undefined, '>'], ['tag', 'p', 'name', 0, 'p']],
    [['empty link'], [0]],
    [['</a>', '<', '/', 'a', '>'], ['tag', 'p', 'p', 'name', 'p']],
    [['.'], [0]]
]

fromPattern(pattern)

Get pattern from RegExp as string.

isPattern(x)

Detect if x is an instance of RegExp.

token(start, content|contents, end = start, skip)

Build pattern string from parameters.

console.log(token('"'));

tokenGroup(start, content|contents, end = start, skip)

Build pattern string from parameters as a group of start, content and end.

console.log(tokenGroup('"'));

toPattern(string, opt = 'g')

Convert pattern string to RegExp instance.

x

List of regular expression’s special characters except \.