[R6RS] Unicode scalar value escape sequences
Tue Mar 1 12:07:37 EST 2005
> Marc> Well strings would still use the "..." notation, so instead of
> Marc> writing (string? #\a) you'd write (string? "a"), and instead
> Marc> of (char->integer #\a) you'd write (char->integer "a"), and instead
> Marc> of (string-ref "abc" 1) you'd write (substring "abc" 1 2), or
> Marc> you could keep the string-ref procedure and define it as [...]
> Well, sure. But given that you have all kinds of procedures that
> operate on strings of length 1 only, I don't see how you're making the
> character data type go away in any real sense---you still effectively
> have a separate type. It's just that the type is wedged into the
> language in a way that, to me, makes way less sense than the current
How would you define (char-upcase (integer->char #x00df))?
What about (char-ci<? (integer->char #x00df) #\T)?
Why is there a string and character type in Scheme, but there is no
digit type to go with the exact integer type? This asymmetry
bother's me. Why is there a need to distinguish #\a and "a" but not
to distinguish the digit 9 and the number 9? The only good reason I
see is mutability, but as I said before I think strings should be
> This thread started with me asking about making the syntax for scalar
> values in string literals agree with what you have in Gambit-C. You
> never replied to that---any opinion?
I'm against it. I think the syntax would be strange, overly complex
Here's another proposal. Keep the \xhh and \uhhhh syntaxes for
compatibility with C and Java (i.e. exactly 2 and 4 hexadecimals
respectively) but require a delimiter for \U and allow any number of
"\U20;\U00000021;\Ua;" = " !\n"
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