Re: Is the Writing on the Wall for Ada?

[Marin David Condic <nobody@noplace.com>]

O.K. But my question remains, "Does anybody use them in *practice*?" 
When I've needed a record field for something like Person_Name and 
wanted some fixed allocation on it, I use a String and if/when I needed 
to know where the string stopped, I use a "Last_Non_Blank ()" function. 
But in most of the instances where I need something like this, I just 
jump to Unbounded_String and am done with it.

I understand that Bounded_String has some technical advantages, but in 
my experience, the instant I'm on a PC at some astronomical number of 
megahertz/gigahertz with more memory than I can shake a stick at, 
Unbounded_String and all its technical disadvantages compared to 
Bounded_String just seem to not amount to a warm bucket of spit. Hence 
I'm wondering if people actually have/do use it on anything like a 
regular basis.

Maybe I'm unusual and most Ada programmers make use of Bounded_String 
thirteen times a day. My usual question is: "Do I care about speed or 
determinism in this application?" When "Yes" => String; When "No" => 
Unbounded_String; Do other programmers have a When "Maybe" => 
Bounded_String; branch?

I'm sure we could sit here all day and dream up circumstances when 
Bounded_String might make some sense, but I'm wondering if in real-world 
experience, people make use of it. Remember that one of the motivations 
behind RISC architectures was that researchers discovered that in some 
instances, specific CISC architecture instructions were not being 
exploited at all by compilers and started asking the question "Should we 
waste the silicon to implement it if nobody is using it?" That's the 
question I'm asking here.


MDC


Jean-Pierre Rosen wrote:
> They are great if you want an abstract data type *implemented as* as string of variable length.
> 
> For example, if you have Person_Name, Person_Address, etc.
> You want them to be different types, they have a maximum length, and
> a variable current length. Instead of deriving from String, you get these
> types by an instantiation of Bounded_String.
> 


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