What is Expressiveness in a Computer Language

David Squire David.Squire at no.spam.from.here.au
Tue Jun 20 10:29:36 EDT 2006


Andreas Rossberg wrote:
> Rob Thorpe wrote:
>>>
>>>> No, that isn't what I said.  What I said was:
>>>> "A language is latently typed if a value has a property - called it's
>>>> type - attached to it, and given it's type it can only represent values
>>>> defined by a certain class."
>>>
>>> "it [= a value] [...] can [...] represent values"?
>>
>> ???
> 
> I just quoted, in condensed form, what you said above: namely, that a 
> value represents values - which I find a strange and circular definition.
> 

But you left out the most significant part: "given it's type it can only 
represent values *defined by a certain class*" (my emphasis). In C-ish 
notation:

     unsigned int x;

means that x can only represent elements that are integers elements of 
the set (class) of values [0, MAX_INT]. Negative numbers and non-integer 
numbers are excluded, as are all sorts of other things.

You over-condensed.

DS

NB. This is not a comment on static, latent, derived or other typing, 
merely on summarization.




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