Here's an error that I very nearly made recently, simplified down to the bare (and rather trivial-looking) essentials:

for($i = 0; $i < 10; $i++) {
  &foo();
}

# foo: print the first three positive integers
sub foo
{
  for($i = 1; $i <= 3; $i++) {
    print $i;
  }
  print "\n";
}

[download]

Uh, not good.

The problem was coming back to Perl after spending a lot of time writing PHP code, where variables inside functions are locally scoped by default. This story has a happy ending: my long-standing habit of using strict immediately caught the error, and saved me quite a bit of debugging time.

It occurs to me that this example might be useful when you're trying to convince people, especially ex-PHP types, that strict is good.

--
:wq

In reply to Implicit context conversion error, brain.pl line 666 by FoxtrotUniform

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