Curly Braces for Multiple Value Assignment?

>
> http://www.cc.gatech.edu/fac/mark.guzdial/squeak/notes/curlybraces.html       
>
> In the email archived here Mark seems to indicate that at some point you
> could use the curly brace syntax as if it were a sort of list
> comprehension.  Brian Rice pointed me toward this link as I was asking
> about idioms for variable swapping on the IRC channel.
>
> This doesn't work in trunk as the parser doesn't like it for multiple
> reasons.  I tried it in 3.7 and the parser complains less but still
> doesn't like the := (or _) after the brace.  Is this mistranslated
> speculation by Mark or was this a feature lost eons ago?  If lost, was
> there a reason against it?  I've found myself pining for the ability to
> nicely handle returning multiple values as well as stuff like variable
> swapping that would be nicely covered (given certain assumptions about
> the implementation) by this.
>
> Wouldn't some form of list comprehension be a nice check box for Squeak?
>
> Ken