Assuming I understand your question, you're looking for a generic "Best Practices" rule you can apply to using "if-elsif" to ensure that *if* you have a warning (or die)in the "EXPR" of (one of) the elsif, *then* the line number reported for that warning (or death) will be accurate.

Is that correct?

Assuming youre requirement is to keep using if-elsif, then i don't think there's anything you can do -- short of waiting for a new version of perl that does a better job of reporting the line number.

One thing you can do, is replace all occurences of this...

elsif (EXPR) BLOCK
...with this...
else { if (EXPR) BLOCK }

Using the test case from Node #42078 as an base for an example, use this instead... 

#!/usr/bin/perl -w
$def = '';
undef $notdef;
if($def eq 'foo') {   # Line 4
    
} else { if ($def eq 'bar') {
} else { if ($notdef eq "RHS") { # Line 7
} } }

[download]
That should accurately cite the warning on Line 7.

Personally, I don't think it's really that big a deal .. just make sure you keep in mind this problem for the future, and if you ever notice any warnings/deaths cited with a line number of some "if (EXPR)" code, then skim down and see if there's an "elsif" that might be the real culprit.

In reply to Re: if-elsif weirdness by hossman
in thread if-elsif weirdness by leriksen

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