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Re: [Scheme-reports] Fwd: Symbol escapes - clarification

On Mon, Jan 9, 2012 at 7:30 AM, John Cowan <cowan@x> wrote:
> Vincent Manis scripsit:
>> > I'm confused. The syntax in sec 7.1.1 appears to say that a symbol
>> > element is any character except | or \. That seems inconsistent with
>> > John's explanation above.
> You're right.  I've added a fix on trunk to add <hex inline escape> to the
> definition of <symbol element>, making the formal syntax consistent with
> the prose.

Ah, OK.  I was mainly looking at the 7.1.1 formal syntax, so I was confused
that \-escape wasn't valid in |-escapes.  Now it is clear.

If '|' delimits the symbol, can the following prose in 7.1.1 be improved?
That's also the source of confusion.

  Identifiers, dot, numbers, characters, and booleans are terminated
  by a <delimiter> or by the end of the input.

I can't come up with a good wording, but it needs to say something about
vertical-bar-escaped identifiers delimits itself (is it a correct English?)

It may also be possible to add '|' to <delimiter>, which makes it clear
that (123|a|.|b|) reads (123 a . b), for example.

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