Luke Palmer wrote:
Says not:

   Boo
   Boo
   Boo
   ...

This is clear, but I would expect the output

   Boo
   42

because the return value of foo is a ref to a block that
makes the caller return 42. This is written in my current
Perl6 as

&foo:( : --> Block --> 42)

The question is when exactly this call chain is invoked:

  1) when it is assigned to $code? Or,
  2) when &postfix:<( )> is invoked on $code?

I prefer 2) because it better fits my understanding of
referential semantics. About the relationship to the lazy
versus eager trade-off I'm unsure. So 1) is also a good
choice.

With this in mind, I wonder how \ and -> are related. Is

  $x = 3;
  $rw = -> $x;

valid syntax? And does it mean that

  $rw = 7;
  say $x; # prints 7

This can be construed as the eager version of

  $x = 3;
  $rw = -> { $x };

  $rw = 7;
  say $x; # means: say $x();

A block in a chain of references is a stop mark in a chain of refs.

  $x  = 3;
  $r  = -> $x;
  $rr = -> $r;

  say $rr();  # prints 3, because say $r; also prints 3

  $rr = 7;
  say $r;  # prints 7
  say $x;  # prints 3

Looks like we have found a candidate for the transparent ref creator!
And I hope Juerd likes it. After all it looks *pointy* :)

PS: A chain of refs can thus be reduced to the leaf lvalue with
    ([()] $rr) = 23; which stores a new value in $x. This might even
    warrant the special case of ([] $rr) = 23;
--
TSa (Thomas Sandla▀)

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