Don't get me started on \d! Whoever decided to include "something that might be understood as a digit in a language/charset I've never ever heard of" in \d made a huge huge mistake. Out of ten thousands of \d, there's maybe one where this nonsense is what was meant. I do believe even now it's not too late to fix this insanity. The change would fix many times more scripts/modules than it would break.

And what I meant regarding the speed is the difference between 

my $foo = qr/.../;
my $bar = qr/..../;
...
while (<>) {
 ...
 if (/$foo(?:$bar)+/) {
...

[download]
and 
my $foo = qr/.../;
my $bar = qr/..../;
my $foobar = qr/$foo(?:$bar)+/;
...
while (<>) {
 ...
 if (/$foobar/) {
...

[download]
In the later case the stringification and the compilation of a longer regexp happens just once.

Jenda
Enoch was right!
Enjoy the last years of Rome.

In reply to Re^8: Common Perl Pitfalls by Jenda
in thread Common Perl Pitfalls by Joe_

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