Re: Challenges of adding octal and hexadecimal escape sequences in strings

[Mohammad-Reza Nabipoor]

Hi, Jose!

On Fri, Oct 30, 2020 at 05:51:44PM +0100, Jose E. Marchesi wrote:
> 
> I don't think that is the desired behavior.  If we define Poke strings
> as NULL-terminated, it is obvious they are not to contain any NULL
> byte.  Now, we can achieve that by two ways:
> 
> a) By doing what we do now, i.e to ignore any part of the string after a
>    NULL character, in case one is inserted, or
> 
> b) To emit an error whenever a 0 byte is attempted to be stored in a
>    string value.
> 
> Supposing we wanted to switch to b), at the moment the only ways to
> create a string value in Poke are:
> 
> b1) Using a string literal, and
> b2) using a cast from uint<8> to string
> 
> The first case is easy to implement: just emit a compile-time error if a
> string literal contains a null character.
> 
> For the second case we have two choices: either to raise an exception
> when `8UB as string' is executed, or to keep the current behavior of
> generating an empty string "", but the latter would be an exception to
> the rule.
> 
> That's why I prefer a) to b): it is more orthogonal, and can be
> explained by a single rule without needing any exceptions to the rule.
> Also, it comes handy to shorten strings :D

What about a third way:

c) Keep Poke strings as NULL-terminated. Treat using of NULL character in string
   literals as compilation error.

The user cannot access data beyond the first NULL character, and having bytes
beyond that character doesn't make any sense.


Regards,
Mohammad-Reza