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Re: Why are byte ports "ports" as such?

This page is part of the web mail archives of SRFI 91 from before July 7th, 2015. The new archives for SRFI 91 contain all messages, not just those from before July 7th, 2015.

Thomas Bushnell BSG <tb@becket.net> writes:

> We *do* have something we can call characters: characters.
> You might find them useless, but their semantics are quite clear.

It's not clear at all. Please explain what do you mean by characters.

> Storage is irrelevant.  An implementation would be free to store
> characters however it wished.  char->integer and char<? can return
> whatever the implementation pleases.  I would rather drop them, since
> they have nothing really to do with characters.

Then it's impossible to implement a UTF-8 encoder. There is an
infinite number of potential characters, and there is no way to
examine what a given character means.

Similarly it's impossible to implement a UTF-8 decoder. There is
no way to construct characters from code points.

Now, if you come with a set of routines for manipulating the code
point structure of a character, I don't believe that the terminology:
calling it a character instead of a string, and calling the elements
code points instead of characters, is so essential to break
established practice of using code points or even lower level code
units as Scheme characters.

   __("<         Marcin Kowalczyk
   \__/       qrczak@knm.org.pl
    ^^     http://qrnik.knm.org.pl/~qrczak/