From: Tim Hunter <cyclists@...>
Date: 2003-08-26T21:07:19+09:00
Subject: Re: Specification of Ruby regex?

On Tue, 26 Aug 2003 16:15:38 +0900, Ronald Pijnacker wrote:

>> > Hi all,
>> >
>> > I was just wondering... Is there any place where Ruby's Regex
>> > capabilities are described?
>> >
>> > E.g. it seems that /\w{3}/ matches at least three consecutive
>> > characters, but I do not seem to be able to locate any exact
>> > documentation on this.
>> >
>> > Any idea's?
>>
>> Pickaxe is your best friend (ideally, the hardcopy). Some information
>> may be found here:
>> http://www.ruby-doc.org/docs/ProgrammingRuby/html/tut_stdtypes.html
>> 
>> Scroll down to "Regular Expressions" sections.
>> 
>> Gennady.
> 
> There is certainly a lot of information there, but I have the feeling that
> there are things not discussed. My example "r {m}" is not mentioned as
> such, but works anyway.
> 
> A better example would have been /o . I have seen it being used, but it is
> not documented. If it does what I've been told it does, it is good to know
> about.
> 
> Another is /(?: ...)/ . It seems to work, but also is not documented.
> Aparently the Pickaxe book is not exhaustive.
> 
> As I am currently reading "Mastering Regular Expressions", I started
> wondering what exacly is or is not supported by Ruby.
> 
>     Ronald.

In the paper version of the Pickaxe r{m} is described on
page 61. Extensions such as (?:...) on pp. 209-211.

My online version of the Pickaxe (from ruby-doc.org) documents both as
well. For the extensions, click The Ruby Language in the TOC and scroll
down to the Extensions section. Repetition (r{m}) is documented in
Standard Types.