my $foo = 0; print ++$foo + $foo++; prints 3

Treating + as a function is the best way I've found to explain it. 

do { local @_;
     alias $_[0] = ++$foo;  # aliases to $foo
     alias $_[1] = $foo++;  # aliases to anon 1
     &sum                   # 2+1
   }

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In reply to Re^5: Will "$_[0]=shift" always resolve shift first? by ikegami
in thread Will "$_[0]=shift" always resolve shift first? by kyle

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