As a Perl rule in general, assignments and operations take precedence over non-assignments.

In the first case (with out the +0), the precedence for printf "%4d : %3d\n",$ofs,(($ofs+=4)-4)*4 is:

1 -- (($ofs+=4)-4)*4
2 -- $ofs

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Where the expression contained the assignment of $ofs+=4 has a higher precedence over the expression of $ofs by itself.

In the second case, both the $ofs+0 and $ofs+=4 has the same precedence, so the $ofs+0 will be evaluated and pushed onto the stack first, before the $ofs+=4 gets evaluated.

In reply to Re: Order of operations, mutators, aliasing and whammies by Roger
in thread Order of operations, mutators, aliasing and whammies by demerphq

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