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Re: Prefix, not postfix

This page is part of the web mail archives of SRFI 88 from before July 7th, 2015. The new archives for SRFI 88 contain all messages, not just those from before July 7th, 2015.

On 11-Apr-06, at 5:51 PM, Taylor R. Campbell wrote:

I'm posting this merely for the sake of offering another opinion on
legibility; I don't think that any syntax changes in this area are
good, because they can break existing and compliant R5RS code.  For
instance, I've seen this naming convention somewhere: FOO has to do
with an exclusive interval, FOO: with an interval exclusive on the
lower bound and exclusive on the upper bound, :FOO with an interval
inclusive on the lower bound and exclusive on the upper bound, and
:FOO: with an inclusive interval.  For another example, SRFI 42 would
break if the meaning of a colon prefix were changed in Scheme's
lexical identifier syntax, although if any extension were to be made
I'd prefer the colon prefix.

I'm not sure I understand your point. I'm advocating for a colon suffix. SRFI 42 uses a colon prefix on identifiers (which by the way is illegal in R5RS except for a lone colon). So keyword objects using a colon suffix syntax do not hinder in any way SRFI 42 or any R5RS compliant code, but a colon prefix syntax does.

I know that some code has used colon suffixes on identifiers (for example the withdrawn iota: function in SRFI 1), but there are very few uses of this and it is not portable anyway so I don't think this argument has much weight.