Pls help with a Regex

I have this sort of information in a text file

19:00	STEPPING THE WORLD: Gr Islands - Corfu.

and I am trying to build a regex that will put

19                    into backreference 1
00                    into backreference 2
STEPPING THE WORLD    into backreference 3
Gr Islands - Corfu into backreference 4

I have built this ^(\d{2})(?::|\.)(\d{2})\s(.*)(?::\s)(.*).$ and it works fi
ne

but I want that if I have something like this
19:00	STEPPING THE WORLD

I would still have backreference 1,2, and 3 filled.

Any help

David Joseph Bonnici wrote:
> I have this sort of information in a text file
>
> 19:00	STEPPING THE WORLD: Gr Islands - Corfu.
>
> and I am trying to build a regex that will put
>
> 19                    into backreference 1
> 00                    into backreference 2
> STEPPING THE WORLD    into backreference 3
> Gr Islands - Corfu into backreference 4
>
> I have built this ^(\d{2})(?::|\.)(\d{2})\s(.*)(?::\s)(.*).$ and it works 
fine
>
> but I want that if I have something like this
> 19:00	STEPPING THE WORLD
>
> I would still have backreference 1,2, and 3 filled.

Then make the last part optional:

^(\d{2})(?::|\.)(\d{2})\s(.*?)(?:(?::\s)(.*).)?$
--------------------------------^-^^^-------------^

or slightly simplified:

^(\d{2})[:.](\d{2})\s(.*?)(?::\s(.*))?$

--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl

David Joseph Bonnici <djb@global.net.mt> wrote:
> I have this sort of information in a text file
>
> 19:00	STEPPING THE WORLD: Gr Islands - Corfu.
^^^
^^^

That was a tab character in your post, I plan to make use of that.


> and I am trying to build a regex that will put
>
> 19                    into backreference 1
> 00                    into backreference 2
> STEPPING THE WORLD    into backreference 3
> Gr Islands - Corfu into backreference 4
>
> I have built this ^(\d{2})(?::|\.)(\d{2})\s(.*)(?::\s)(.*).$ and it works fine[/co
lor]


It looks like "saying what you want to keep"[1] is hard...


> but I want that if I have something like this
> 19:00	STEPPING THE WORLD
>
> I would still have backreference 1,2, and 3 filled.


"saying what you want to throw away"[2] may be easier.

If the string is already in $_, then:

my @fields = split /:\s*|\t/;

Figuring out how to get rid of the dot from the end of the last
field is left as an exercise for the reader.




Randal has a saying:

[1] If you want to say what to keep then use m// in list context.

[2] If you want to say what to throw away then use split().

--
Tad McClellan                          SGML consulting
tadmc@augustmail.com                   Perl programming
Fort Worth, Texas

Thanks it works fine.

"Gunnar Hjalmarsson" <noreply@gunnar.cc> wrote in message
news:3d5e2rF6pqfjvU1@individual.net...
> David Joseph Bonnici wrote: 
>
> Then make the last part optional:
>
>     ^(\d{2})(?::|\.)(\d{2})\s(.*?)(?:(?::\s)(.*).)?$
> --------------------------------^-^^^-------------^
>
> or slightly simplified:
>
>     ^(\d{2})[:.](\d{2})\s(.*?)(?::\s(.*))?$
>
> --
> Gunnar Hjalmarsson
> Email: http://www.gunnar.cc/cgi-bin/contact.pl