RegExp.prototype.toString() - JavaScript | MDN

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Object.prototype.toString()

The RegExp object overrides the toString() method of the Object object; it does not inherit Object.prototype.toString(). For RegExp objects, the toString() method returns a string representation of the regular expression

Empty regular expressions and escaping

Since toString() accesses the source property, an empty regular expression returns the string "/(?:)/", and line terminators such as \n are escaped. This makes the returned value always a valid regex literal.

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This page was last modified on Aug 3, 2025 by MDN contributors.

[Symbol.matchAll]()

[Symbol.replace]()

[Symbol.hasInstance]()

__defineGetter__()

__defineSetter__()

__lookupGetter__()

__lookupSetter__()

propertyIsEnumerable()

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