[r6rs-discuss] [Formal] should allow quoting non-letters in identifiers

[Per Bothner]

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Submitter: Per Bothner <per at bothner.com>
Type of issue: Enhancement
Priority: Minor
Component: Lexical syntax
Version of the report: 5.92
Summary: allow escaping non-constituent characters in identifiers

Common Lisp and many Scheme implementations provide a way
to escape certain characters to force them to be viewed as
constituents of identifiers (and hence symbols).

The draft does allow <inline hex escape> to serve this need,
but such hex escapes are not very readable or user-friendly.

Traditionally, one or both of these have been used:

|123|
\123

We may not want to reserve | for this purpose, but \ is already
in use for escapes, and it is easy to extend it.  I suggest:

<initial> --> <constituent> | <special initial>
   | <inline escape>

<inline escape> -->
   | <inline hex escape>
   | \<character name>;
   | \<any character whose category is none of Lu, Ll, Lt, Lm, or Lo>
-- 
	--Per Bothner
per at bothner.com   http://per.bothner.com/