Re: [Sbcl-devel] Line termination character for source files

[Christophe R. <cs...@ca...>]

Raymond Wiker <Ray...@fa...> writes:

>         Would it be an idea to make SBCL be a bit more tolerant about
> line termination?

I don't think so.  What would be nice, I think, would be to extend the
currently very rudimentary external-format support, so that one could
specify to COMPILE-FILE and LOAD that the file you're dealing with has
(:newline-style :cr) or somesuch.

Why don't I like "tolerance"?  Well, newline characters are
significant in various contexts: within "strings", |escaped symbols|
and (my favourite) after a ~ in a format string.  If we start getting
tolerant we actually have to think about what some reasonable default
(for all users) behaviour is, how to make users aware that something
odd has been smoothed over (for those cases where the default is wrong
but the user isn't aware of the problem), and how to customize it.  By
being brittle, people are immediately aware of an issue: an issue
which is larger than just newline termination -- it affects natural
language comments (and source code!) too.

That issue is how to turn a bunch of bytes (on disk or off the
network) into a bunch of characters -- and I really think that this is
such a complex issue that I'm even a bit nervous about forgiving bad
encodings in comments; certainly, converting all byte values of 13 to
Newline is completely the wrong answer: just wait until Brian
Spilsbury or some other far-East hacker wants comments in Korean...

Cheers,

Christophe