# Special Tokens

<table><thead><tr><th>Function</th><th width="179.33333333333331">RegExp equivalent</th><th>Explanation</th></tr></thead><tbody><tr><td><code>exactly`(yes/no)`</code></td><td><code>\(yes\/no\)</code></td><td>Match the given string literally, escaping all special characters</td></tr><tr><td><code>lineFeed</code></td><td><code>\n</code></td><td>Match a line feed character</td></tr><tr><td><code>not.lineFeed</code><br><code>not(lineFeed)</code></td><td><code>[^\n]</code></td><td>Match anything other than a line feed</td></tr><tr><td><code>carriageReturn</code></td><td><code>\r</code></td><td>Match a carriage return character</td></tr><tr><td><code>not.carriageReturn</code><br><code>not(carriageReturn)</code></td><td><code>[^\r]</code></td><td>Match anything other than a carriage return</td></tr><tr><td><code>backspace</code></td><td><code>[\b]</code></td><td>Match a backspace character</td></tr><tr><td><code>not.backspace</code><br><code>not(backspace)</code></td><td><code>[^\b]</code></td><td>Match anything other than a backspace</td></tr><tr><td><code>tab</code></td><td><code>\t</code></td><td>Match a tab character</td></tr><tr><td><code>not.tab</code><br><code>not(tab)</code></td><td><code>[^\t]</code></td><td>Match anything other than a tab</td></tr><tr><td><code>verticalWhitespace</code></td><td><code>\v</code></td><td>Match a vertical whitespace character</td></tr><tr><td><code>not.verticalWhitespace</code><br><code>not(verticalWhitespace)</code></td><td><code>[^\v]</code></td><td>Match anything other than a vertical whitespace</td></tr><tr><td><code>formFeed</code></td><td><code>\f</code></td><td>Match a form feed character</td></tr><tr><td><code>not.formFeed</code><br><code>not(formFeed)</code></td><td><code>[^\f]</code></td><td>Match anything other than a form feed</td></tr><tr><td><code>nullChar</code></td><td><code>\0</code></td><td>Match a null character</td></tr><tr><td><code>not.nullChar</code><br><code>not(nullChar)</code></td><td><code>[^\0]</code></td><td>Match anything not null</td></tr><tr><td><code>octal`123`</code><br><code>octal('123')</code></td><td><code>[\123]</code></td><td><p><strong>DEPRECATED</strong></p><p>Match a character with the given code point in base-8 †</p></td></tr><tr><td><code>not.octal`123`</code><br><code>not(octal('123'))</code></td><td><code>[^\123]</code></td><td><p><strong>DEPRECATED</strong></p><p>Match anything other than the specified character</p></td></tr><tr><td><code>hex`3f`</code><br><code>hex('3f')</code></td><td><code>\x3f</code></td><td>Match a character with the given code point in base-16 ‡</td></tr><tr><td><code>not.hex`3f`</code><br><code>not(hex('3f'))</code></td><td><code>[^\x3f]</code></td><td>Match anything other than the specified character</td></tr><tr><td><code>unicode`3ef1`</code><br><code>unicode('3ef1')</code></td><td><code>\u3ef1</code></td><td>Match a character with the given code point in base-16 ‡</td></tr><tr><td><code>not.unicode`3ef1`</code><br><code>not(unicode('3ef1'))</code></td><td><code>[^\u3ef1]</code></td><td>Match anything other than the specified character</td></tr><tr><td><p><code>control`j`</code></p><p><code>control('j')</code></p><p><code>control`J`</code></p><p><code>control('J')</code></p></td><td><p><code>/\cj/</code></p><p><code>/\cJ/</code></p></td><td><p>Match a control character with value equal to the given letter's character value modulo 32</p><p>Only a letter from <code>a</code> to <code>z</code> or <code>A</code> to <code>Z</code> is allowed</p></td></tr><tr><td><p><code>not.control`j`</code></p><p><code>not(control('j'))</code></p><p><code>not.control`J`</code></p><p><code>not(control('J'))</code></p></td><td><p><code>/[^\cj]/</code></p><p><code>/[^\cJ]/</code></p></td><td>Match anything other than the specified control character</td></tr></tbody></table>

#### † Notes on `octal`

Octal escape sequences (\ followed by one, two, or three octal digits) are deprecated in string and regular expression literals. Please avoid using them as much as possible.

The RegExp output of `octal` is always wrapped in a character class to disambiguate it from capture group back-references.

The maximum allowed value is `0o377`, which is equivalent to `0xff`.

#### ‡ Notes on `hex` and `unicode`

Both have the same effect, but `hex` uses the single-byte escape sequence `\xff` if possible, while `unicode` always uses the 2-byte sequence `\uffff`.