Re: Regexp map weirdness

One thing you should read is death to dot start. You should change the following regex:

m/t(.*?)e/, m/wri(.*?)en/);
[download]

to:

m/t([^e])e/, m/wri([^e])en/);
[download]

The above regex is much more efficient, and it says what you really mean.

The 15 year old, freshman programmer,
Stephen Rawls

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Re: Re: Regexp map weirdness by Hofmator (Curate) on Aug 02, 2001 at 21:44 UTC
You probably meant `m/t([^e])e/, m/wri([^e])en/);` didn't you? :)) And a quick benchmark shows the speed advantage: `Benchmark: timing 300000 iterations of dotstar, negchar... on string q +/tddddde/ dotstar: 1 wallclock secs ( 1.37 usr + 0.00 sys = 1.37 CPU) @ 21 +8658.89/s (n=300000) negchar: 0 wallclock secs ( 0.95 usr + 0.00 sys = 0.95 CPU) @ 31 +5457.41/s (n=300000) Rate dotstar negchar dotstar 218659/s -- -31% negchar 315457/s 44% --` [download] The longer the captured part, the better performs negchar. In the case of a failure, both methods take approx. the same time. -- Hofmator	[reply] [d/l] [select]

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Re: Re: Regexp map weirdness
by Hofmator (Curate) on Aug 02, 2001 at 21:44 UTC

You probably meant m/t([^e]*)e/, m/wri([^e]*)en/); didn't you? :)) And a quick benchmark shows the speed advantage:

Benchmark: timing 300000 iterations of dotstar, negchar... on string q
+/tddddde/
   dotstar:  1 wallclock secs ( 1.37 usr +  0.00 sys =  1.37 CPU) @ 21
+8658.89/s (n=300000)
   negchar:  0 wallclock secs ( 0.95 usr +  0.00 sys =  0.95 CPU) @ 31
+5457.41/s (n=300000)
            Rate dotstar negchar
dotstar 218659/s      --    -31%
negchar 315457/s     44%      --
[download]

-- Hofmator

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