diff options
author | Nobuyoshi Nakada <nobu@ruby-lang.org> | 2023-01-11 21:56:42 +0900 |
---|---|---|
committer | Nobuyoshi Nakada <nobu@ruby-lang.org> | 2023-01-11 23:25:28 +0900 |
commit | a468213917b793c47d98e172b2f0a3853460c367 (patch) | |
tree | 11e22c0c4e594b75861ab51a0555797018876f09 /doc/regexp.rdoc | |
parent | ac8cf010bc2cad78f4e2cf182c475effdb12b181 (diff) | |
download | ruby-a468213917b793c47d98e172b2f0a3853460c367.tar.gz |
[DOC] Mention the conditional regexp
Diffstat (limited to 'doc/regexp.rdoc')
-rw-r--r-- | doc/regexp.rdoc | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/doc/regexp.rdoc b/doc/regexp.rdoc index 92c7ecf66e..c6c983d1d9 100644 --- a/doc/regexp.rdoc +++ b/doc/regexp.rdoc @@ -405,6 +405,15 @@ a single one that matches any of the expressions. Each expression is an /\w(and|or)\w/.match("furandi") #=> #<MatchData "randi" 1:"and"> /\w(and|or)\w/.match("dissemblance") #=> nil +== Condition + +The <tt>(?(</tt><i>cond</><tt>)</tt><i>yes</i><tt>|</tt><i>no</i><tt>)</tt> +syntax matches _yes_ part if _cond_ is captured, otherwise matches _no_ part. +In the case _no_ part is empty, also <tt>|</tt> can be omitted. + +The _cond_ may be a backreference number or a captured name. A backreference +number is an absolute position, but can not be a relative position. + == Character Properties The <tt>\p{}</tt> construct matches characters with the named property, |