Re^3: regex gotcha moving from 5.8.8 to 5.30.0?

in reply to Re^2: regex gotcha moving from 5.8.8 to 5.30.0?
in thread regex gotcha moving from 5.8.8 to 5.30.0?

I usually use re 'debug'; when debugging regular expressions, but I'm not sure it's helpful in this case.

The usual suspects are .* or .*?, because they start by matching the whole string and then backtracking to match less. Can't you replace them with [^;]* or similar?

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

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Re^4: regex gotcha moving from 5.8.8 to 5.30.0? by mordibity (Acolyte) on Feb 10, 2021 at 00:16 UTC
Thx for the idea; I just tried it (using `[^;]?` instead of `.?` in the two locations) but it didn't really change the (crude) runtimes -- 5.8.8 is over twice as fast as 5.30.0 (~14sec vs ~37sec) on the fake data, and 10x as fast (~6sec vs 105sec) on the real data...	[reply] [d/l] [select]

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