A few holes (imho) in the ecosystem of libraries

[Guillaume Piolat]

On Monday, 15 May 2023 at 13:38:12 UTC, Andrew wrote:
> On Monday, 15 May 2023 at 13:04:57 UTC, Guillaume Piolat wrote:
>> 2. A I/O abstraction really suitable for parsing/emitting
>
> Regarding your second point, I noticed this was limiting me 
> recently, so I've been working in the evenings on a 
> proof-of-concept for what this could look like if added to 
> Phobos in the same style as ranges: 
> https://forum.dlang.org/thread/okoaghstghyxapqcwbtr@forum.dlang.org

I'll take an example.

My current TGA parsing looks like this ugly:

     bool getImageInfo(IO* io, IOHandle _handle)
     {
         // Taken right from stb_image.h

         bool err;
         _dataOffset = _io.read_ubyte(_handle, &err);
         if (err)
             return false;

         _cmapType = _io.read_ubyte(_handle, &err);
         if (err || _cmapType > 1)
             return false; // only RGB or indexed allowed

         _imageType = _io.read_ubyte(_handle, &err);
         if (err) return false;


        /// ...more parsing...
     }

What I would really want is:

     bool getImageInfo(IO* io)
     {
         _dataOffset = _io.read_ubyte();
         _cmapType = _io.read_ubyte();
         _imageType = _io.read_ubyte();
         return !_io.error;
     }


Can't use exceptions since downstream user will use that on 
WebASM, -betterC not having class etc.
And I cannot use your library for similar reasons, it uses the 
runtime, it uses exceptions, it has generic names etc. We have a 
lot of such libraries, but we have to keep in mind people use D 
because they are performance-oriented and they may have druntime 
constraints. Ideally the D runtime would be pay-as-you-go and 
infinitely portable, but that's not the current state of things.