Regular Expression Properties

The following table displays a summary of the regular expression properties. Note that several of these properties have both long and short (Perl-like) names. Both names always refer to the same value. Perl is the programming language from which JavaScript modeled its regular expressions. Detailed descriptions of each property follow the table.

Property	Description
$1, ..., $9	Parenthesized substring matches, if any.
$_	See input.
$*	See multiline.
$&	See lastMatch.
$+	See lastParen.
$'	See leftContext.
$'	See rightContext.
global	Whether to test the regular expression against all possible matches in a string, or only against the first.
ignoreCase	Whether to ignore case while attempting a match in a string.
input	The string against which a regular expression is matched.
lastIndex	The index at which to start the next match.
lastMatch	The last matched characters.
lastParen	The last parenthesized substring match, if any.
leftContext	The substring preceding the most recent match.
multiline	Whether to search in strings across multiple lines.
rightContext	The substring following the most recent match.
source	The text of the pattern.