Re: assign to magic name-of-function variable instead of "return"

[David L. Nicol]

> > make $__ mean "An alias for the
> > L-value of what the subroutine return value will get assigned to, or
> > ${undef} if we're not invoked as an R-value."

> A /much/ better syntax, in [John Mastros's] humble opinion.  However,
> $__ must act sanely when we're called as an inner function (IE foo(bar(42))).


Given

     sub foo($){ $__ = blarg(shift ); side_effect()};


     $fred = foo(bar(42))

     \$__ within bar would be \${foo's block::$_[0]};
     \$__ within foo would be the same as \$fred 
     \$__ within blarg is also \$fred because $__ is blarg's lvalue
     \$__ is \${undef} within side_effect because it is not called as an rvalue.

if we allow $__ to have meaning more than one deep we'll be in action-at-a-distance
land for sure.

 
> [john porter] thinks that's unnecessarily baroque.  Just let $__ be an alias
> to the return value stack, the place where return() puts its
> args anyway.  

That defeats the purpose of optimizing away the assignment from the return stack.

> In fact, shouldn't it be @__ ?

     ($a, $b, $c) = foo($_);    # ref($__ ) is now ARRAY

This new variable could take the place of C<want>; or C<want> could mean C<ref($__)>





-- 
                      David Nicol 816.235.1187 [EMAIL PROTECTED]
                      www.tmcm.com, dammit