Name

RegExp — regular expressions for pattern matching

Inherits from

Object → RegExp

Literal Syntax

/pattern/attributes

Constructor

new RegExp(pattern, attributes)

Arguments

pattern

A string that specifies the pattern of the regular expression or another regular expression.

attributes

An optional string containing any of the “g”, “i”, and “m” attributes that specify global, case-insensitive, and multiline matches, respectively. The “m” attribute is not available prior to ECMAScript standardization. If the pattern argument is a regular expression instead of a string, this argument must be omitted.

Returns

A new RegExp object, with the specified pattern and flags. If the pattern argument is a regular expression rather than a string, the RegExp() constructor creates a new RegExp object using the same pattern and flags as the specified RegExp. If RegExp() is called as a function without the new operator, it behaves just as it would with the new operator, except when pattern is a regular expression; in that case, it simply returns pattern instead of creating a new RegExp object.

Throws

SyntaxError

If pattern is not a legal regular expression, or if attributes contains characters other than “g”, “i”, and “m”.

TypeError

If pattern is a RegExp object, and the attributes argument is not omitted.

Instance Properties

global

Whether the RegExp has the “g” attribute.

ignoreCase

Whether the RegExp has the “i” attribute.

lastIndex

The character position of the last match; used for finding multiple matches in a string. ...

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