Of late, I'm not sure that's so true. The most recent perls (the last year anyway) ensures that all potentially used capture variables are cleared regardless of whether the expression succeeds. So /((...)|(...))/ addresses $1, $2, and $3. Since the fix, you can guarantee that each variable will have a sane value. You still can't guarantee $4 -> on though. I think. Or could those be guaranteed already?

In reply to Re^4: Disabling regexp optimizations? by diotalevi
in thread Disabling regexp optimizations? by diotalevi

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