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Re: [Scheme-reports] Symbol escapes - clarification
Peter Bex scripsit:
> Yeah, # is pretty special. The spec should probably leave that
So it is.
> Maybe a whitelist of characters that are definitely allowed
> in symbols?
There is such a list (of ASCII characters only) in 2.1.
> Several (most?) schemes actually try to read until the next
> s-expression separator and convert it to a number. If that fails, it's
> a symbol and taken as-is. I'm not sure this behaviour should be
> standardized as it's very "loose" and poorly defined.
The R7RS-draft behavior is that a sequence of letters, numbers, specified
ASCII symbols, and non-ASCII characters in certain general categories
is an identifier, *provided* it does not have a prefix which is a number.
This is easy to state verbally, but makes for a messy BNF.
Henry S. Thompson said, / "Syntactic, structural, John Cowan
Value constraints we / Express on the fly." cowan@x
Simon St. Laurent: "Your / Incomprehensible http://www.ccil.org/~cowan
Abracadabralike / schemas must die!"
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