Re: [nongnu] elpa/geiser bb9d5cb200: geiser-impl--normalize-method: quick fix for previous change

[Jose A Ortega Ruiz <jao@gnu.org>]

On Fri, Jan 28 2022, Stefan Monnier wrote:

>> yes, that works, but i find it ugly to use eval explictly for the sake
>> of not using "a list-that-looks-like-a-function":
>
> To me, it's being more honest: we have a variable that holds an ELisp
> expression, so we need `eval` somwehere.
>
>> what are the downsides of the latter?  i understand that i'd be just
>> hiding an implicit eval, but is that all, or am i missing
>> other drawbacks?
>
> There's no serious drawback, no.  Here are some minor drawbacks:
> - In Common-Lisp and Scheme '(lambda () 5) does not evaluate to
>   something recognized as a function.  Currently ELisp does, but I think
>   it's something better avoided.  I hope in some distant future we can
>   make the types `function` and `cons` be a mutually-exclusive.
> - the function value `(lambda () ,v) returns a function that will
>   evaluate v using the old dynamically-scoped dialect which we're trying
>   to phase out.

ok, that sounds mildly persuasive, and it's always good to plan for the
next 50 years...

>> (isn't, loosely speaking, hiding evals one of things macros
>> buy us?
>
> `eval` is used sometimes in macros, but most macros neither use nor hide
> `eval`, AFAIK, no.

i was thinking of the fact that a (non-hygienic) macro essentially
produces a list that is then evaluated for me implicitly.  but anyway,
it was just a loose association.

>> ... the version without eval looks more readable to me).
>
> My own taste is reflects in the fact that my local Emacs rejects
> (lambda ...) as a valid function value ;-)

i've pushed a patch using eval... why, it'd be a shame if you couldn't
use geiser! ;)

thanks,
jao
-- 
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