On Mon, 18 Apr 2005, Lloyd Sartor wrote: > Jerry Kassebaum wrote on 04/17/2005 06:56:29 AM: > > > > $x=10; > > > > $x=$x++; > > > > print "$x\n"; > > > > $x=10; > > > > $y=$x++; > > > > print "$x\n"; > > > > #Results: $x=10, $x=11. > > #I understand it, but I think it's weird anyway. > > > > The first result ($x=10) puzzles me. Are not the $x on the LHS and RHS > refering to the same scalar? I would think that $x would be assigned the > value of $x (10), and then be post-incremented, resulting in 11. > > Explanation?
The code is equivalent to: $x = 10; $tmp = $x++; $x = $tmp; Think about how a more complex expression would need to be compiled: $x = 10; $x = $x++ + $x++; turns into $x = 10; $tmp1 = $x++; $tmp2 = $x++; $x = $tmp1 + $tmp2; Setting $x to 21. The $tmp variables are just stack locations containing intermediate results of subexpressions. Cheers, -Jan _______________________________________________ Perl-Win32-Users mailing list Perl-Win32-Users@listserv.ActiveState.com To unsubscribe: http://listserv.ActiveState.com/mailman/mysubs
