If you want to keep the captured bits, assign them to variables in your code, rather than relying on them being retained in global variables:
my( $bit1, $bit2, $bit3 ) = /(..)(..)(..)/;
Any code you call -- library routines etc. -- after you run the regex, but before you want to use its results, might also use the regex engine and overwrite those temporary global variables. So, don't rely on it.
(Also, whether any of us agree with you or not, its been that way a very long time and isn't likely to change; so best get used to the idea :) )
In reply to Re^3: non-capture mode sometimes erases previous capture
in thread non-capture mode sometimes erases previous capture by raygun
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