>  I believe Fr?d?ric is suggesting that it is equivalent to an implicit 
>  upvar on the name (in the scope of the called proc), but guarantees that 
>  the variable exists.  Using upvar currently provides no such guarantee 
>  because the variable name is a weak reference.
>  >      proc foo v { ... }
>  >      foo $&bar
>  >
>  > is roughly equivalent to:
>  >
>  >      proc foo vName { upvar 1 $vName v; ... }
>  >      foo bar
>  >
>  > Is that correct?

This is very similar to what we already have implemented in L.  The &var
syntax is just syntatic sugar for the implied upvars as needed in the
callee; the caller, it means pass the name of the variable instead of
the value.

Seems to work quite well.
-- 
---
Larry McVoy                lm at bitmover.com           http://www.bitkeeper.com

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