Re: I wonder if I'm missing something...

I think your approach is equivalent to mine except:

- the transducers are explicitly symbols rather than opaque objects which the implementation gets to define (and there are potentially hundreds of distinct ones)

- 'it should also support custom data types' turns it from a small soluble problem to a huge one with no general solution at all.

On and the displaced array thing: (a) ick, just no, (b) this already solves David's problem (just make the displaced array be an array of (unsigned-byte 8)s and write-sequence does what you want.

If you want C I hear that C compilers are quite commonly available now.

--tim

> On 7 Nov 2025, at 20:01, Yuri Davidovsky <[email protected]> wrote:
> 
> 
> 
>> On 7 Nov 2025, at 20:21, Tim Bradshaw <[email protected]> wrote:
>> 
>> Here is a sketch (which I may have mentioned here previously) of how functionality could be added to CL which would enable fast I/O of, for instance, vectors of floats without destroying the language by allowing arbitrary type punning, and also dealing with things like ensuring things are written in defined byte orders.
> 
> Interesting. I was thinking of something different. Essentially any byte stream could be read (and written to) arbitrary data types using primitives like:
> 
> (read-byte stream) — as is now.
> (read-byte stream :uint32) — will read an unsigned 32 bit int.
> (read-byte stream :float) — you start to get the idea.
> 
> You could do the same with read-sequence by supplying the type of data to read and an array of appropriate type. It should also support custom data types.
> 
> Also when creating a displaced array it should allow casting to a different type.


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