single valued variables

[drw@cullvax.UUCP]

"SVDSD::PETCHER@ti-eg.CSNET" writes:
> I am not an Ada expert, so correct me if I'm wrong, but...
> When one declares a variable range to be (true..true) is that not in itself a 
> contradiction?  A variable that can have only one value is, by definition, not 
> a variable, but a constant.  In that context, it seems a compiler should 
> create a constant, issue a diagnostic for any subsequent code that attempts to 
> change the constant, and generate no executeable code for same.  I realize the 
> most likely place for a single-valued variable to occur would be in 
> instantiation of a generic, but if a generic so instantiated does not treat 
> single-valued variables as constants then the program is basically in error.

I'm not well-versed in Ada, but methinks that such a variable is
inherently different from a constant in that one can/should be able to
assign to it--although there is only one value that can be assigned,
so it doesn't do very much!  Anything else leads to serious
nonuniformity.

Dale
-- 
Dale Worley		Cullinet Software
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