Re: ADA Popularity Discussion Request

[kevin.cline@gmail.com (Kevin Cline)]

Georg Bauhaus <sb463ba@l1-hrz.uni-duisburg.de> wrote in message news:<chupnc$9t1$1@a1-hrz.uni-duisburg.de>...
> Kevin Cline <kevin.cline@gmail.com> wrote:
> 
> : Explicit static typing ala Ada and C++ definitely has a cost,
> 
> Yes. (And you get something in return, too?)
> 
> : because it makes the code longer,
> 
> Sometimes I prefer a few explicit words to brevity when brevity would
> hide things away.
> 
> : and also makes it more brittle.
> 
> Hm. Brittle? Your example could be a design issue. 

> In Ada you could have
> written
> 
>    generic
>       type FPT is digits <>;
>    function compute(x, y: FPT) return FPT;
> 
> or
> 
>    generic
>       type FPT is digits <>;
>    package Computations is ...

Yes, you could have, if you had thought of it before your team wrote
100,000 lines of code.  But we're not omniprescient.  Sometimes
requirements change, and sometimes we make mistakes.   This
flexibility also comes with a cost -- it makes the code harder to
read.  Everyone knows what digits<> means, but the first time we see
FPT we'll have to go look it up.  Should we also create a type for
discrete inventory quantity, or just use integer?  Well, it's possible
that we could need to go to 64 bits, but right now we don't have
enough memory to expand them all to 64 bits, so better create a IQTY
type.  And so it goes... soon you have dozens or hundreds of data
types, and no one knows what they all mean, and the code is obscured
by type conversions.