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From: J. mp on 30 Nov 2009 21:07
Hi,

I really can't figure out how regular expressions work, and since I
don't use them frequently is easier to ask...

I have the follwow string

++((100))++askjasdjksjdkasdkjk++((200))++skdjsjd

I need a reg expression that extracts only the first number inside the
first ++(( ))++ and ignore the rest..., in this case I need to return
100


thanks
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From: David Masover on 30 Nov 2009 21:55
On Monday 30 November 2009 08:07:26 pm J. mp wrote:
> I have the follwow string
>
> ++((100))++askjasdjksjdkasdkjk++((200))++skdjsjd
>
> I need a reg expression that extracts only the first number inside the
> first ++(( ))++ and ignore the rest..., in this case I need to return
> 100

Since I can't figure out why you'd ever want to do that in a real app, I have
to ask: Is this a homework assignment?

Well, I'd rather not assume, so I'll give you a partial answer: Regular
expressions don't return things, they match things. You can't write a regular
expression (that I know of) which will match only what you're asking for,
unless you assume things about that specific string. Especially in homework,
assuming things like that is a Bad Idea.

There is a solution, and it includes regular expressions, but they are not the
whole story.

From: Marnen Laibow-Koser on 30 Nov 2009 22:05
J. mp wrote:
> Hi,
>
> I really can't figure out how regular expressions work,

So you're giving up and expecting us to do your work for you? Come on!
You could at least try.

> and since I
> don't use them frequently is easier to ask...

Yes, ask. Ask irb. Ask http://www.rubular.com . But don't you dare ask
this list until you've made an attempt. Begging others to write code
because you're too lazy to try is not cool!


>
> I have the follwow string
>
> ++((100))++askjasdjksjdkasdkjk++((200))++skdjsjd
>
> I need a reg expression that extracts only the first number inside the
> first ++(( ))++ and ignore the rest..., in this case I need to return
> 100
>
>
> thanks

Best,
-- 
Marnen Laibow-Koser
http://www.marnen.org
marnen(a)marnen.org
--
Posted via http://www.ruby-forum.com/.

From: J. mp on 30 Nov 2009 22:23

you're both right. That was a dumb question. I will try to find it by
myself. Thank you.
--
Posted via http://www.ruby-forum.com/.

From: Marnen Laibow-Koser on 1 Dec 2009 00:40
J. mp wrote:
>
> you're both right. That was a dumb question. I will try to find it by
> myself. Thank you.

Good luck. If you get stuck, help is available. Regexes are lots of
fun once you understand them!

Best,
-- 
Marnen Laibow-Koser
http://www.marnen.org
marnen(a)marnen.org
--
Posted via http://www.ruby-forum.com/.

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