OK, here are mine. 

open OUT ">$output_file" or die $!;

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or its companion: 
print OUT, "foo bar baz\n";

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Although I've noticed a certain improvement with the first one of these ever since I started using the "extended form" of open and lexical handles: 
open my $out, '>', $output_file or die $!;

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Here's another one (I've already given up all hope with this one): 

push @foo = 'bar';  # aaaaargh!!!

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Why? WHY???

A whole raft of them all have to do with precedence mixups: 

my $foo = $bar or $baz;
print "You have $foo foo" . $foo==1?'':'s' . ":\n";
my @frobozz = map foo($_) or bar($_), @baz;

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(That's three precedence bugs, one per line. At least.)

Correction: Make that 4.

And the forgotten semi-colons (2 bugs, at least): 

eval {
  what() if $i == do { this() };
}
die $@ if $@;
my $coderef = sub {
  my $name = shift;
  return "don't worry $name, be happy\n";
}
print $coderef->('Pustular');

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...though my editor usually helps me with these.

And the meanest of them all: 

eval { "require $foo; 1" } or die "Where's $foo?\n";
print $foo->happiness();

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Ouch.

There are many more that routinely chomp my monkly butt, but reliving all these bugs at once is beginning to give me the shakes...

the lowliest monk

In reply to Re: Stupid mistakes I repeatedly make by tlm
in thread Stupid mistakes I repeatedly make by brian_d_foy

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