From: Robert Klemme <shortcutter@...>
Date: 2008-04-07T17:06:41+09:00
Subject: Re: Regex and non-greedy matching?

2008/4/7, Marc Heiler <shevegen@linuxmail.org>:
> I have a slight problem. I have strings with some tags such as
>
>  '<b><lightblue>name:</></b>'
>
>  I need to match "name:" and "lightblue"
>  In other words:
>   - What is between <> </>
>  and
>   - What is inside the first <> right next to "name:"
>
>  The following regex does not work:
>
>  '<b><lightblue>name:</></b>' =~ /<([a-zA-Z]+)>(.+?)<\/>/
>
>   $1  # => "b"
>   $2  # => "<lightblue>name:
>
>  $2 should only be name:
>  and $1 should only be lightblue

Constructing a regexp to match more specific often helps:

irb(main):001:0> s='<b><lightblue>name:</></b>'
=> "<b><lightblue>name:</></b>"

irb(main):002:0> md = %r{<b>\s*<([^>]*)>([^<]*)</>}.match s
=> #<MatchData:0x7ff973f4>
irb(main):003:0> md.to_a
=> ["<b><lightblue>name:</>", "lightblue", "name:"]

irb(main):004:0> md = %r{<b>\s*<([^>]*)>\s*([^<]*)</>}.match s
=> #<MatchData:0x7ff85b54>
irb(main):005:0> md.to_a
=> ["<b><lightblue>name:</>", "lightblue", "name:"]
irb(main):006:0>

See how this works without reluctant quantifier?

Cheers

robert

-- 
use.inject do |as, often| as.you_can - without end