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Re: SRFI-108/SRFI-109 special characters

This page is part of the web mail archives of SRFI 108 from before July 7th, 2015. The new archives for SRFI 108 contain all messages, not just those from before July 7th, 2015.

Per Bothner scripsit:

> On 11/18/2012 01:22 PM, John Cowan wrote:
> >I strongly prefer XML-style with braces.
> Both forms use both braces and brackets, so I'm unclear
> whether you mean "XML-style with braces for literal text"
> or "XML-style with braces for escaped expressions".

I meant the former, eliminating the whole idea of initial expressions.
They seem to be insufficiently justified in this draft (to be sure, it
says "examples needed", which I can only agree with).  If there are no
initial expressions, then square brackets need not be used, and braces
suffice for both quasi-expressions and unquoted expressions.  Given that
there is substantial disagreement in the Scheme world about what, if
anything, square brackets should be for, I consider it wise to avoid them.

But if initial expressions are to be kept, I don't see why the example
#&cname[&{exp1 exp2}text} should be expanded into something involving
an empty string.  Does #&cname[&{exp1}&{exp2}] expand to ($quasi-value$
cname "" exp1 "" exp2 "")?  Surely not.  If the two notations are said
to be equivalent, they should be *truly* equivalent, and the user left
to choose between them without any desugaring artifacts.

> I don't believe either "xml-style" or "scribble-style" (or certain other
> possible variations) directly conflict with SRFI-105 or brackets as
> alternative parens.

Hmm, right.  Okay, never mind those arguments -- but I still think
it's better not to have square brackets.

I think your remark that Scribble-style is not really compatible with
Scribble is enough to sink the idea.  It's hard to maintain two subtly
different lexical syntaxes in one's head.  The XML-style is really not
much like XML, and creates no mental conflicts.

John Cowan  cowan@xxxxxxxx   http://ccil.org/~cowan
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