Hello dominic01,

The Camel Book (4th Edition, 2012) has a section on “Time Efficiency” which contains the following (p. 692):

Short-circuit alternation is often faster than the corresponding regex. So:

print if /one-hump/ || /two/;

[download]

is likely to be faster than:

print if /one-hump|two/;

[download]

at least for certain values of one-hump and two.

Also, if your regex is more likely to find a space than a punctuation character, test for the space first. Only profiling will show whether these kinds of tweaks make significant improvements, but they’re worth a try.

Hope that helps,

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

In reply to Re: Improving performance by Athanasius
in thread Improving performance by dominic01

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