Re^5: filtering an array

Likewise, the for is unnecessary in this code too:

for (@positions) {@positions = map $_->[0], @positions;}
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It should just be:

@positions = map $_->[0], @positions;
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because map iterates over the array you give it. Even better, you could write:

$_ = $_->[0] for @positions;
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here we are making the for implicit in map explicit.

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Re^6: filtering an array by prbndr (Acolyte) on Sep 01, 2012 at 23:15 UTC
perl still has a problem with this: `@positions = grep $_->[1] =~ /ac/i, @positions;` with the same error Use of uninitialized value in pattern match (m//)	[reply] [d/l]
Re^7: filtering an array by philiprbrenan (Monk) on Sep 01, 2012 at 23:19 UTC
One or more of the elements of the array @positions is undefined. The easiest way to check this is like this: `use Data::Dump qw(pp); pp([@positions]);` [download] This will give you a printout of the value of each element in array @positions. I expect we will see that some are "undef" meaning undefined. It will be these elements that are causing the problem.	[reply] [d/l]
Re^8: filtering an array by prbndr (Acolyte) on Sep 01, 2012 at 23:39 UTC
i don't see any that are "undef. that's a little strange. the data dumper output prints: 9031, "A" etc. etc. this is a little strange...	[reply]