in reply to Newbie reg.exp question!

Well, if it's always the first 11 characters you want, there's no need to use a regexp. Use substr instead: 
use strict;
my $string="AB123456789this_code_is_untested";
my $match=substr $string, 0, 11;

[download]
If you really want to use a regexp (which is less efficient), use something like: 
$string=~/^([a-zA-Z]{2}\d{9}).*/;
print $1;

[download]

CU
Robartes-

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Re: Re: Newbie reg.exp question!
by RuneK (Sexton) on Nov 13, 2002 at 13:54 UTC
    Hi again,
    The 2 chars and 9 digits code I got the last time has taken on a life of it's own. It now seems that there is not only one possible instance of the substring in a string, but possible more. The code I'm using to locate the sunstring is the following:

    ($number) = $line =~ m{ ( [A-Z]{2}\d{9} ) }ix;

    [download]

    The $line can now contain more substings. How do I ensure that the reg.xp. get's all the instances?. I cannot do a split because the data is entered by mortal users who tend to have no sense of order. So a string could look like:

    "So I found SP236645744 in reference ED331234576, but not
    in IJ558897567."

    Hope you Gurus can help,
    Rune
[reply]
[d/l]
      In that case, you would use a slightly modified version of the regexp: 
      use strict;
my $string="this_PM123456789_code_is_untested";
$string=~/([a-zA-Z]{2}\d{9})/;
print $1;

      [download]
      This will find the first occurence of your string.

      CU
      Robartes-

[reply]
[d/l]

      almost the same as above:

      my($chars_nums) = $string =~ m{
  ( [a-z]{2}\d{9} )   # capture 2 chars + 9 digits
}ix;

      [download]
[reply]
[d/l]
      Hi again, Thanks anyway, but I found a working solution my self. Like this:

      (@instances) = $line =~ m/[A-Z]{2}\d{11}/g;

foreach $elem (@instances)
   {
    print $elem . ",";
   }

      [download]

      It gives me every occurance of the substring in the string.
      BR,
      Rune
[reply]
[d/l]
        Help again,
        My script just evolved. Now I need to support an extend string that looks like this:

        C[CCNNNNNNNNNNN]
C= Char
N= Number

        [download]
        The former solution looked like this: 

        @list = $line =~ m{ ( [A-Z]{2}\d{11} ) }gx;

        [download]
        How can I support the special characters in the string? I tried like this, but it didn't return anything:

        @list = $line =~ m{ ( [A-Z]{1}\[[A-Z]{2}\]\d{11} ) }gx;

        [download]
        Could someone please help and explain me how to do it correctly so that I don't have to ask next time?


        Thanks,
        Rune
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