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A comment on the regexen:

# regex to add a comma after each char # i believe you can think of it starting # at the second character since # ?<= means look to the left of the current # position # the . means to look at one character # the () are required to capture each character $show_choices =~ s/(?<=.)/,/g; $show_choices =~ s/,$//g; # remove the last comma

Actually, there is no capturing being done in the first regex; the parentheses are there only for grouping, i.e. to show where the positive look-behind assertion ends. (Try adding a $1 to the replacement part, and you will get a series of error messages beginning Use of uninitialized value $1.)

The first regex could also be written as:

$show_choices =~ s/(.)/$1,/g;

which does capture each character.

The two regexen can be combined into one using a negative look-ahead assertion:

$show_choices =~ s/(.)(?!$)/$1,/g;

See “Look-Around Assertions” under Extended Patterns in perlre.

Hope that helps,

Athanasius <°(((><contra mundum Iustus alius egestas vitae, eros Piratica,


In reply to Re: Perl replacement for choice.com by Athanasius
in thread Perl replacement for choice.com by onelander

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