> > returns an rvalue

FWIW: I think this code is easier to understand and demonstrates your point 

  DB<194> sub tst { my $x=\(shift()); ++$$x }

  DB<195> $a=10
 => 10

  DB<196> tst $a
 => 11

  DB<197> tst $a
 => 12

  DB<198> $a
 => 12

[download]
I get the same results using the equivalent splice(@_,0,1)

That's not documented in the perldocs for shift or splice and I think it's due to the way Perl holds and replaces variables in @_, they just don't loose their aliasing magic when shifted.

Maybe Perl avoids copying of the values for performance reasons.

Interesting...

But since it's not documented, I doubt that this is reliable behavior.

Cheers Rolf

( addicted to the Perl Programming Language)

In reply to Re^3: Order of execution of functions in list by LanX
in thread Order of execution of functions in list by vsespb

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