Re: Re: Common Regex Gotchas

[Anonymous Monk]

in reply to Re: Common Regex Gotchas
in thread Common Regex Gotchas

If I am not mistaken the Benchmark module is plagued by the "$& and friends". That means it makes the regexes slow by defualt. That means that the benchmarks you take are disproportionate and useless, since the ineffectiant single instance of $& ruins any optimizations perl can make on the substitution.

[chipmunk]

Happily, that doesn't appear to be the case. I don't see any occurence of the $& et al. variables in the code for Benchmark.pm

The real problem here is the use of /e on the substitution, when this would work just as well and be much more efficient: s/(\w+)/\U$1/g;

[dws]

I don't see any occurence of the $& et al. variables in the code for Benchmark.pm

I think what our Anonymous friend means is that if one of the routines being benchmarked uses $&, then all routines suffer (unfairly) from the overhead.

[chipmunk]

I'm pretty sure that the AM was referring to the module itself, especially since none of the code in this thread actually uses $& et al.