guile-devel
[Top][All Lists]
Advanced

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

Re: GNU Guile 3.0.0 released


From: Arne Babenhauserheide
Subject: Re: GNU Guile 3.0.0 released
Date: Thu, 16 Jan 2020 22:35:44 +0100
User-agent: mu4e 1.2.0; emacs 26.1

Andy Wingo <address@hidden> writes:

> We are delighted to announce GNU Guile release 3.0.0, the first in the
> new 3.0 stable release series.
…
> The Guile web page is located at http://gnu.org/software/guile/

That’s awesome! Thank you for your work!

> Changes in 3.0.0 (since the stable 2.2 series):
…
> ** Just-in-time code generation
>
> Guile programs now run up to 4 times faster, relative to Guile 2.2,
> thanks to just-in-time (JIT) native code generation.  Notably, this
> brings the performance of "eval" as written in Scheme back to the level
> of "eval" written in C, as in the days of Guile 1.8.

This is awesome! I hope it finally alleviates the problems faced by Lilypond!

> ** Interleaved internal definitions and expressions allowed

I love that! It removes one of the early stumbling points I had with
Guile which pushed me to avoid inner defines. I only realized later how
much more readable code gets with inner defines.

Can we get this into the Scheme standard, too?

> ** `guard' no longer unwinds the stack for clause tests
>
> SRFI-34, and then R6RS and R7RS, defines a `guard' form that is a
> shorthand for `with-exception-handler'.  The cond-like clauses for the
> exception handling are specified to run with the continuation of the
> `guard', while any re-propagation of the exception happens with the
> continuation of the original `raise'.
…
> Guile now works around these issues by running the test portion of the
> guard expressions within the original `raise' continuation, and only
> unwinding once a test matches.  This is an incompatible semantic change
> but we think the situation is globally much better, and we expect that
> very few people will be affected by the change.

Is this semantic change a change from previous Guile or a deviation from
the Scheme standard?

Best wishes,
Arne
--
Unpolitisch sein
heißt politisch sein
ohne es zu merken



reply via email to

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