Re^3: Use of uninitialized value in pattern match (m//)

Those are actually warnings - the script keeps running, and probably does what you intended overall (whereas an error would cause the script to halt immediately). I expect that the warnings happen on the last iteration of the "for" loop:

for $line (<FILE>) {
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The part in parens produces an anonymous array that the "for" will iterate over, and the last element of that array the "undef" element from the last attempt to read from the file handle and encountering 'eof'. If you used a while loop instead, you wouldn't enter the block (lines 25 and 26 would not be reached) on that last attempt to read from the file.

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Re^4: Use of uninitialized value in pattern match (m//) by Anonymous Monk on Mar 18, 2015 at 01:24 UTC
The part in parens produces an anonymous array that the "for" will iterate over, and the last element of that array the "undef" element from the last attempt to read from the file handle and encountering 'eof'. If you used a while loop instead, you wouldn't enter the block (lines 25 and 26 would not be reached) on that last attempt to read from the file. um, none of that :) if the match fails $participant is undef , when you try to print var which is undef you get uninitialized warning `$ perl -MData::Dump -we " open $fake, q{<}, \qq{a\nb\nc\n\n}; for(<$fa +ke>){ dd($_); }" "a\n" "b\n" "c\n" "\n"` [download]	[reply] [d/l]
Re^5: Use of uninitialized value in pattern match (m//) by graff (Chancellor) on Mar 18, 2015 at 01:36 UTC
Thanks - that should teach me to avoid posting guesses...	[reply]