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Side effects of (??{CODE}) in Regex (Rubber Ducking)

LanX — Sat, 18 Apr 2026 19:00:44 +0000

I wanted to test the effect of the /o modifier on embedded code (context), and was very surprised about the second version using (??{CODE}) (FWIW adding /o makes the first...

Re^3: counting backward (optimize foreach reverse low .. high

Anonymous Monk — Mon, 20 Apr 2026 02:46:54 +0000

Somebody finally made a feature request for the optimization, but it didn't get any traction: Optimize reverse RANGE....

Re: metacpan fastapi can't find the Config module

InfiniteSilence — Sun, 19 Apr 2026 19:48:47 +0000

I'm with hippo; not sure why you are doing this but here are some ideas. First, MetaCPAN has its own module. Borrowed directly from Met...

Re^23: Reusing a complex regexp in multiple spots, escaping the regexp

dave_the_m — Sat, 18 Apr 2026 16:07:05 +0000

state is implemented sensibly. The /o implementation needs updating to behave like state. It's a hacky leftover from when the perl internals were first altered to be thread-safe. Dave....

Re^22: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Sat, 18 Apr 2026 13:47:18 +0000

It's much clearer now, much appreciated! 🙏🏻 Op-Tree manipulation is indeed "creative". (I remember Merlyn complaining that the flip-flop was implemented in a similar way...

Re^21: Reusing a complex regexp in multiple spots, escaping the regexp

dave_the_m — Sat, 18 Apr 2026 12:30:23 +0000

On unthreaded builds, after the pattern has been assembled and compiled once, the op tree is modified so that on subsequent executions, all the assembly ops are skipped. On threaded builds, all the as...