Re: Why use C++?

["Jed" <jehdiah@orbitway.net>]

"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message 
news:150vz10ihvb5a.1lysmewa1muz4$.dlg@40tude.net...
> On Thu, 11 Aug 2011 03:20:55 -0500, Jed wrote:
>
>> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message
>> news:1d8wyhvpcmpkd.ggiui9vebmtl.dlg@40tude.net...
>>> On Wed, 10 Aug 2011 17:37:28 -0500, Randy Brukardt wrote:
>>>
>>>> There are uses for wrapping types, but they are far less likely than 
>>>> wanting
>>>> overflow detection. The default should be to catch errors, not turn 
>>>> them
>>>> into different ones.
>>>
>>> The OP mentioned image processing, the behavior frequently needed 
>>> there is
>>> saturated integer arithmetic, which is nether ranged nor modular.
>>>
>>> As for modular types, wrapping is the mathematically correct 
>>> behavior,
>>> it is not an error.
>>>
>>> You just cannot provide every possible arithmetic at the language
>>> level.
>>>
>>
>> What do you think the practical level of limitation is?
>
> Types that cannot be constructed by the operations of the types algebra
> provided by the language. Richer the algebra is, less built-in types
> needed.

Will you give an example to clarify please?

>
>> Were you thinking "beyond integers" with your statement?
>
> There is nothing special in integer types, except that for the types
> algebra you need ordinal numerals (i.e. at least one integer type).

I know a little bit (enough to "be dangerous") of Intel assembly, and it 
looks like C/C++ integer types are a direct reflection of what is at that 
level. Even the fact that by default, integer literals are signed. So in 
that respect, I think they are special. They are chosen for efficiency as 
a direct reflection of hardware (I'm not saying all hardware is the same, 
mind you).

>
>> What kinds of integer types would
>> you like to see built-in to a hypothetical ideal language?
>
> As little as possible. Usage of predefined integer types makes design 
> more
> fragile. E.g. it is bad when somebody uses Ada's Integer, or C++ int 
> (OK,
> in C++ there is no other option), instead of introducing a type 
> reflecting
> the application semantics rather than the decision of some compiler 
> vendor
> motivated by other concerns.
>

You have to build those types though based upon the built-in ones, yes? 
If so, aren't modular, wrapping and overflow-checked equally good for 
something and all worthy of being in a language? Of course there is 
signed, unsigned and the different bit widths as candidates also. And are 
not those built-ins good to use "raw" in many cases? Are you suggesting 
that a language have NO types? There is assembly language for that (and 
the instruction set pretty much dictates what types you have to work with 
at that level).