Donald G Porter wrote:
>  Here's a thought to consider.
>  
>  Given that the poll says only a solution targetted for 9.0 will be
>  accepted, an incompatibility (preferably as small as possible) is
>  permitted.
>  
>  So we could combine the word-prefix-syntax architecture of {expand}...
>  with the use of the somewhat more eye-pleasing prefix $* .
>  
>  In current Tcl, a word that begins with literal $* will also begin with
>  literal $* after substitution.  If we made use of $* as the expansion
>  prefix for a word in Tcl 9, then anyone expecting literal $* would be
>  forced to produce it via some substitution.  For example,
>  
>  	set punctuation $*&!^@#
>  	
>  would have to become something like
>  
>  	set punctuation \$*&!^@#
>  or
>  	set punctuation \u0024*&!^@#
>  	
>  That's the extent of the incompatibility.  Probably less impact than
>  choosing ` .  Perhaps less than the :: in command names incompatibility
>  from the 7 -> 8 transition.
>  
>  Otherwise the modified proposal would be the same as TIP 157.  Just
>  replace the prefix string {expand} proposed there with the prefix 
>  string $* .

Maybe that would be the occasion to introduce double/multiple 
substitution, i.e

	set foo 1
	set bar foo
	puts $$bar
	=>  1

Currently this yields
	
	puts $$bar
	=>  $foo

If we choose to extend the semantics of $ substitution at the price of 
some incompatibility, then at least let's push the idea to its limits. I 
don't know what it implies WRT the Endekalogue, though.

OTOH this doesn't solve command expansion, i.e {expand}[command 
args...]. I don't think *[command args...] is an option, as it may clash 
badly with expr. The {expand} syntax is nice and consistent on this 
point, as it applies at the beginning of all words. Sorry but I don't 
get the point about its supposed ugliness; as a user I find it perfectly 
readable and explicit (much more than having to decipher or - aargh - 
write eval/list/lrange voodoo).



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