Re: Ada Idioms Progress Preview

[lutz@iks-jena.de (Lutz Donnerhacke)]

* Ole-Hjalmar Kristensen wrote:
>One thing which can be said in favour of having a terminator character is
>that it frees you from having to store the length explicitly.

This requires an out-of-band terminator, which does not exists in C.
Instead they prefer to use a valid character they do not need at the moment.

But the real problem of a terminator character is creating a view:
In order to reference a substring you have to create a full copy of the
substring because you have to insert the terminal character. Inserting it
directly into the main version would cause serve damage.

Dealing with copies:
  - is time inefficient.
  - is semantical different modulo modifications.
  - is space inefficient.
  - requires heap space instead of stack space.

>The length of a string is usually different from the size of the array
>used to store the string.

It's not necessary to provide a buffer to hold any possible string of a
given type if you can pass complex objects to or from a function. C can only
pass primitive types and therefore switched to passing pointers of implicit
terminated arrays.