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Re: [Scheme-reports] Symbol escapes - clarification

Alaric Snell-Pym scripsit:

> I'd prefer that ALL characters are legal in symbols, and we carefully
> distinguish "allowed in symbols" and "allowed unescaped in the written
> representation of symbols" (bearing in mind that a written symbol from a
> full Unicode system might be read in by an ASCII-only system) in
> discussion :-)

Well, I think the most we can require, given our policies on characters and
strings, is that a character is legal in a symbol iff it's legal in a string.
There's nothing we can do about the fact that some systems will support
non-ASCII characters (or other restricted repertoires) and others will not.

In my original proposal, I tried to work around this problem by having some
systems support \x3034; as a single-character symbol and others as a
seven-character symbol, but the edge cases don't work properly: you wind up
with some symbols having two string equivalents and vice versa.

> The text on identifiers in 2.1 says that . is not an identifier; does
> that mean I *cannot* write (define |.| 123) and then (+ |.| 456)?


> If I get a moment I will carefully read all relevant sections of the
> report and suggest some fixes...

Sounds like a plan.

John Cowan   cowan@x    http://ccil.org/~cowan
The known is finite, the unknown infinite; intellectually we stand
on an islet in the midst of an illimitable ocean of inexplicability.
Our business in every generation is to reclaim a little more land,
to add something to the extent and the solidity of our possessions.
        --Thomas Henry Huxley

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