Re^3: undef==defined sometimes? (body question)

Why don't you just return nothing at all on error, and get over the non-problem problem?

There was really no point in writing code here in hindsight. So ...

Added code for the uninitiated ...

use Data::Dumper;

my @p = give();
my $p = give();

print Dumper( \@p , $p );

sub give
{
  #  Case of error.
  return;
}
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Comment on Re^3: undef==defined sometimes? (body question) Download Code

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Re^4: undef==defined sometimes? (body question) by perl-diddler (Chaplain) on May 03, 2008 at 11:14 UTC
Well -- I could, but then the calling function would get garbage if I used it in an assignment. The function was supposed to return a list and only returned undef as an error condition (which wasn't the same as returning an empty list). The undef was reserved for 'illegal operations', like an attempt to compare two strings where one string was undefined. Otherwise, if nothing was found, but no error occurred, it returned a list of size 0 ("()"). If I didn't explicitly return a value, wouldn't the results of whatever the last calculation be returned, essentially returning "left-overs" by accident? I'd rather return 'undef' and have consistently wrong behavior rather than random behavior -- at least if it is consistently wrong, I'm more likely to notice a problem. :-) -l	[reply]
Re^5: undef==defined sometimes? (body question) by ikegami (Patriarch) on May 03, 2008 at 11:29 UTC
If I didn't explicitly return a value, wouldn't the results of whatever the last calculation be returned `return;` return an empty list, just like `return ();`. If the function result is treated as a scalar, it will see undef. If you omit the `return` entirely, then you get the result of the last expression evaluated.	[reply] [d/l] [select]