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Re: Geez...



As your commenting on ports, I'm following up on SRFI 81 list, where
this belongs.

Marc Feeley <feeley@xxxxxxxxxxxxxxxx> writes:

> I actually like the R5RS I/O model and think there are more elegant  
> ways to extend it to support the features that would make it more  
> practical (binary I/O, Unicode text encoding, devices such as  
> sockets, processes, etc).  For example, for binary I/O, these are  
> sufficient
>
> - (read-u8 [port]) reads the next octet from the port
> - (read-subu8vector u8vector start end [port]) reads a sequence of  
> octets into a u8vector
> - (write-u8 [port]) writes an octet to the port
> - (write-subu8vector u8vector start end [port]) writes a sequence of  
> octets from a u8vector

Admittedly, the Port SRFI defines all of two procedures in addition to
those you propose: READ-BLOB-SOME and READ-BLOB-ALL.  If that's what
people want, I'll be happy to elide them, even though both could
typically be implemented more efficiently directly rather than in
terms of the others.

But I have trouble seeing how eliding them would make the SRFI in any
way "more elegant."  Care to elaborate?

> For Unicode text encoding and end-of-line encoding, just add some  
> optional parameters to the port opening procedures to supply the port  
> settings, and a procedure to change the port settings.  For example, with
> named optional parameters (aka keyword parameters):

I don't understand---that exactly what the SRFI does.  It has an
optional transcoder argument that specifies text encoding and EOL.
Moreover, it has procedures to change the buffer mode.  How is this
more elegant?

> - (open-input-file "myfile.txt" char-encoding: 'utf8 buffering: #f)
> - (open-file "myfile.txt" direction: 'input char-encoding: 'utf8  
> buffering: #f)
> - (port-settings-set! myport buffering: #t eol-encoding: 'cr-lf)

Sure, there's a slight difference in the division of labor.  You can
always shift responsibility between the procedures themselves and
their arguments.  I come down in a slightly different place than you
do (and I happen to like my choices better, so there), but it surely
makes very little difference in the size and scope of the specs.

-- 
Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla