It seems like order of execution of some expressions is undefined, including list of arguments to a function call.
1: eval order of args to a sub
2: Why is the execution order of subexpressions undefined?


Now I'm wondering if this is a valid code: 
sub mysub {
my ($a1, $a2) = (shift, shift)
...

[download]
Probably not valid. However I see it's widely used on CPAN: cpan grep
So, question is: is it allowed by perl documentation?

In reply to Order of execution of functions in list by vsespb

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