Re: regex "o" modifier

You can use eval and /o together for rise of performance:

for my $day_week( qw(Mon Tue Wed Thu Fri Sat Sun) ) {
    my $regexp = "^$day_week"; 

    eval 'for my $day (qw (Mon Mon Wed Fri Sat Sun Fri Wed Tue Wed) ) 
+{               
              if($day =~ m/$regexp/o) { # do somthing }           
           }';    
}
[download]

In this case, regexp will be recompiled for each iteration of extern loop, which changes our regexp. But the regexp will not recompile every time into internal loop. It will serve.

      
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SV* sv_bless(SV* sv, HV* stash);

Comment on Re: regex "o" modifier Select or Download Code

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Re^2: regex "o" modifier (use qr//) by Aristotle (Chancellor) on May 07, 2003 at 07:46 UTC
That's a perfect example of what `qr//` was made for. `for my $day_week( qw(Mon Tue Wed Thu Fri Sat Sun) ) { my $regexp = qr/^$day_week/; for my $day (qw (Mon Mon Wed Fri Sat Sun Fri Wed Tue Wed)) { if($day =~ m/$regexp/) { # do somthing } } }` [download] Much clearer and more readable and, yes, more efficient too. tye is right: Never use /o. Makeshifts last the longest.	[reply] [d/l]