So, you're doing ++ multiple times on the same variable in the same statement, and you're getting results that you don't expect.

Time to whip out the manual!

Note that just as in C, Perl doesn't define when the variable is incremented or decremented. You just know it will be done sometime before or after the value is returned. This also means that modifying a variable twice in the same statement will lead to undefined behaviour. Avoid statements like: 
$i = $i ++;
print ++ $i + $i ++;

[download]
Perl will not guarantee what the result of the above statements is.
You're doing just that. You do something that is documented to not guarantee what the result is.

It's fine if you go that way. Just don't ask why you're getting the results you're getting.

In reply to Re: Order of evaluation/interpolation of references by JavaFan
in thread Order of evaluation/interpolation of references by Anonymous Monk

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