Re: [TCLCORE] TIP #292: Allow Unquoted Strings in Expressions

[Brian G. <bgr...@mo...>]

Larry McVoy wrote:
> On Thu, Nov 02, 2006 at 04:24:21PM +0000, dr...@hw... wrote:
>   
>> Brian Griffin <bgr...@mo...> wrote:
>>     
>>>  ABSTRACT 
>>> ==========
>>>
>>>  This TIP proposes allowing unquoted words to be recognized as strings 
>>>  in expressions (*expr*, *if*, *while*). 
>>>
>>>       
>> I would much prefer that unquoted words be recognized as variable
>> names.  The single most common mistake I make when programming
>> in TCL is to omit the $ before variable names in expr.
>>     

I would attribute this kind of mistake to "thinking in C" rather then a 
short coming of Tcl.  I also make the mistake of putting {} around if 
conditions in C, but I'm not going to petition the C standards body to 
accept {} in place of () because of my forgetfulness.


>
> I tend to agree.  And while we're there, is there really any need to
> preserve the fact that you can do
>
> 	set {silly variable name!} "some string"
>
> Wouldn't life be simpler if there was a 
>
> 	tcp configure c-variable-names true
>   

No, it wouldn't!  Again, Tcl is not C!

The point is that the current situation is inconsistent. 

    set foo ASTRING               ;# legal syntax
    set foo "ASTRING"           ;# legal syntax
    if {$foo eq "ASTRING"}  ;# legal syntax
    if {$foo eq ASTRING}     ;# illegal syntax!

This is odd and goes against the EIAS basis of Tcl.  Either accept 
unquoted string in expressions or require quotes everywhere else in 
Tcl.  A third option is to divorce expr from "if", "while", and "for" 
commands, replacing it with a more Tclish conditional expression evaluator.

-Brian