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  1. [ References  ](/en-US/docs/Web)
  2. [ JavaScript  ](/en-US/docs/Web/JavaScript)
  3. [ Reference  ](/en-US/docs/Web/JavaScript/Reference)
  4. [ Standard built-in objects  ](/en-US/docs/Web/JavaScript/Reference/Global_Objects)
  5. [ RegExp  ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp)
  6. [ RegExp.leftContext ($`)  ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/leftContext)

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##  In this article

  * Description 
  * Examples 
  * Specifications 
  * Browser compatibility 
  * See also 

  1. **[ Standard built-in objects ](/en-US/docs/Web/JavaScript/Reference/Global_Objects) **
  2. **[ ` RegExp ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp) **
  3. Constructor 
    1. [ ` RegExp() constructor ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/RegExp)
  4. Properties 
    1. [ ` RegExp[@@species] ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/@@species)
    2. [ ` RegExp.prototype.dotAll ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/dotAll)
    3. [ ` RegExp.prototype.flags ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/flags)
    4. [ ` RegExp.prototype.global ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/global)
    5. [ ` RegExp.prototype.hasIndices ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/hasIndices)
    6. [ ` RegExp.prototype.ignoreCase ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/ignoreCase)
    7. [ ` RegExp.input ($_) ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/input) Deprecated 
    8. [ ` RegExp: lastIn