in reply to Regular Expression Question

If multiple regexes are acceptable, this'll get you a little closer to what you want, I think. The first regex in the if statement matches the alphanumerics and commas, but not leading/trailing commas; the second regex excludes consecutive commas. 

use warnings;
use strict;

while ( <DATA> ) {
    print "$1\n" if /^(\w+[\w,]+\w+)$/ && !/,,/;
}

__DATA__
!@#$as3dfa
,sdfas3df,
asd3fsa,,a3sdf
as3df,asdf3,3asdf,asd3f
sad3fasdjasdfkasdfklas3jf
3sad3fasdjasdfkasdfklas3jf
3sad3fasdjasdfkasdfklas3jf3

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Output is: 

as3dfa
sdfas3df
as3df,asdf3,3asdf,asd3f
sad3fasdjasdfkasdfklas3jf
3sad3fasdjasdfkasdfklas3jf
3sad3fasdjasdfkasdfklas3jf3

[download]

Replies are listed 'Best First'.
Re: Re: Regular Expression Question
by TASdvlper (Monk) on Dec 04, 2003 at 20:06 UTC 
    print "$1\n" if /^(\w+[\w,]+\w+)$/ && !/,,/;

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    So, if I wanted to check for more than 2 consecutive commas (I should have mentioned that in the original post) I would do the following: 

    print "$1\n" if /^(\w+[\w,]+\w+)$/ && !/,{2,}/;

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      Either would work-- !/,,/ exludes strings containing 2 consecutive commas, and !/,{2,}/ excludes strings containing 2-or-more consecutive commas, which amounts to pretty much the same thing for what you want, if I've understood you correctly.
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        Oop, sorry-- misread your question. If you wanted to check for more than 2 commas, you'd want to use either: 
        /(\w+[\w,]+\w+)/ && !/,,,/

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        or this: 

        if /^(\w+[\w,]+\w+)$/ && !/,{3,}/;

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Re: Re: Regular Expression Question
by Not_a_Number (Prior) on Dec 04, 2003 at 21:40 UTC

    Problem is, this doesn't work for very short strings (2 or fewer characters). Add these:

    __DATA__
a
bc

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    dave

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