You are both right, mrpeabody and ikegami - it's not in the specs; but my take on this is that in the expression 
$result = 8 - 4 - 2;

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the term 8 - 4 is a subexpression and the operand for the rightmost substraction operation; from that I deduce that associativity therefore defines the operand and subexpression evaluation order.

That might be a logical fallacy; which one, I wonder?

Anyways, that's how perl does it, although it is not defined in Perl. Of course the implementation could change, and perl could do a breadth-first evaluation of its execution tree and roll a dice for ad-hoc definition of evaluation order. But the optimizer would set things straight again, I guess :-)

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re^10: eval order of args to a sub by shmem
in thread eval order of args to a sub by otto

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