[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Add internal definitions to derived forms

From: Linus Björnstam
Subject: Re: Add internal definitions to derived forms
Date: Wed, 25 Jan 2023 22:38:02 +0100
User-agent: Cyrus-JMAP/3.9.0-alpha0-85-gd6d859e0cf-fm-20230116.001-gd6d859e0

On Wed, 25 Jan 2023, at 16:38, Greg Troxel wrote:

> My reaction, without thinking much, and being fuzzy on a lot of things
> is that part of the point of guile is that it is Scheme which to me
> means RnRS conformance.   Of course it's not exactly and every other
> Scheme impl is not exactly.  But mostly I think that's a bug as it leads
> to incompatible programs.

Guile already has some nonstandard syntax extensions. Definitions in expression 
context in some places (all bodies, just not begin), cond extensions etc. I had 

> Does the new feature advance the goal of guile as an extension language?

It makes guile more approachable for beginners. We have all written convoluted 
cond clauses that could have been a lot clearer with internal definitions.

> Is this heading for inclusino in the next RnRS?

No, but...

bodies are now specified using letrec*. Allowing internal definitions is a 
small step away, but the only one I heard mentioning it was Marc. I suspect 
they are moving carefully.

The reason r5rs did not include it was that bodies were specified in terms of 
letrec. That made internal definitions hard to pin down. 

Best regards 

reply via email to

[Prev in Thread] Current Thread [Next in Thread]