regexp-support

regexp-support

check RegExp ( regular expressions ) support

install

npm install regexp-support

Api

allow u check support on other RegExp base class

hasSupportFlag(flag: string, RegExpClass?: typeof RegExp, skipPatternCheck?: boolean): boolean
testFlag(flag: string, RegExpClass?: typeof RegExp, flagsPattern?): boolean

RegExpClass can be Object with create, for some class can't create by new

export interface ICreateRegExp
{
	create(pattern: string, flag?: string, ...argv)
}

demo

import support from 'regexp-support';

console.log(support);

desc

lookAheadPositive, lookAheadNegative

• aa(?=bb)
• aa(?!bb)

lookBehindPositive

• (?<=\$)foo

const RE_DOLLAR_PREFIX = /(?<=\\$)foo/g;
'$foo %foo foo'.replace(RE_DOLLAR_PREFIX, 'bar'); // => '$bar %foo foo'

lookBehindNegative

• (?<!\$)foo

const RE_NO_DOLLAR_PREFIX = /(?<!\\$)foo/g;
'$foo %foo foo'.replace(RE_NO_DOLLAR_PREFIX, 'bar'); // => '$foo %bar bar'

node.js 10

{ flags: 
   { multiline: true,
     m: true,
     global: true,
     g: true,
     ignoreCase: true,
     i: true,
     sticky: true,
     y: true,
     unicode: true,
     u: true,
     dotAll: true,
     s: true,
     freeSpacing: false,
     x: false,
     n: false },
  flagsAll: { g: true, i: true, m: true, s: true, u: true, y: true },
  pattern: 
   { namedCapturingGroups: true,
     namedCapturingGroupsUnicode: true,
     namedCapturingGroupsEmoji: false,
     namedCapturingGroupsBackreference: true,
     namedCapturingGroupsDuplicate: false,
     lookAheadPositive: true,
     lookAheadNegative: true,
     lookBehindPositive: true,
     lookBehindNegative: true },
  hasFlagsProp: true,
  nativeFlags: 'gimsuy' }

node.js 9

by test on RunKit

{ flags: 
   { multiline: true,
     m: true,
     global: true,
     g: true,
     ignoreCase: true,
     i: true,
     sticky: true,
     y: true,
     unicode: true,
     u: true,
     dotAll: true,
     s: true,
     freeSpacing: false,
     x: false,
     n: false },
  flagsAll: { g: true, i: true, m: true, s: true, u: true, y: true },
  pattern: 
   { namedCapturingGroups: false,
     namedCapturingGroupsUnicode: false,
     namedCapturingGroupsEmoji: false } }

node.js 8

by test on RunKit

{ flags: 
   { multiline: true,
     m: true,
     global: true,
     g: true,
     ignoreCase: true,
     i: true,
     sticky: true,
     y: true,
     unicode: true,
     u: true,
     dotAll: true,
     s: true,
     freeSpacing: false,
     x: false,
     n: false },
  flagsAll: { g: true, i: true, m: true, s: true, u: true, y: true },
  pattern: 
   { namedCapturingGroups: false,
     namedCapturingGroupsUnicode: false,
     namedCapturingGroupsEmoji: false } }

link

• http://2ality.com/archive.html?tag=regexp