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Re: `let' vs `let*' (was: Re: How do I pass a variable defined in a wrap
From: |
Emanuel Berg |
Subject: |
Re: `let' vs `let*' (was: Re: How do I pass a variable defined in a wrapping let, to a lambda?) |
Date: |
Tue, 15 Mar 2022 09:30:29 +0100 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) |
Jean Louis wrote:
>> As for `let' vs `let*' in theory `let' is parallel and
>> `let*' sequential but in practice `let*' allows references
>> back to its own bindings, so it is recursive `let' if you
>> will, and `let' isn't ...
>
> In the `dlet' discussion, well... I see it so, dlet is
> creating dynamically bound variables, and thus they should
> be available to all variables inside of `dlet"
>
> (dlet ((first-var 1)
> (second-var first-var))
> second-var)
>
> second-var should be equal to first var
Well, the discussion can go both ways ...
(defvar first-var)
(setq first-var 0)
(dlet ((first-var 1)
(second-var first-var))
(list second-var first-var)) ; (0 1)
> but developer Mattias Engdegård, he changed it for the
> reason that dlet is not dlet*
>
>> commit b72f88518b89560accf740a4548368863e6238e0
>> Author: Mattias Engdegård <mattiase@acm.org>
>> Date: Sun Aug 1 17:05:48 2021 +0200
>>
>> * Make dlet work like let, not let*
>>
>> * Change `dlet` so that it has binding semantics like `let` because that
>> * is what a user would expect and it allows a corresponding `dlet*` to
>> be added later should the need arise. Fortunately the change has no
>> effect where it is currently used.
>
> That is what user would expect. But that is not what I as
> user expect. And nobody of other users complained on that,
> though the definition of dlet is changed.
If there are `let' and `let*' I think it makes sense with
`dlet' and dlet*, and slet/llet and slet*/llet*.
Don't know how much sense `let' and `let*' do tho.
Maybe someone is working on the/a true parallel `let' as we
speak ... well, keep it then I guess :)
> dlet is described with: Like ‘let’ but using
> dynamic scoping.
Poor docstring. Because `let' can do dynamic/special variables
even under static/lexical scope. Maybe one could get away with
just adding the word ALWAYS somewhere ...
--
underground experts united
https://dataswamp.org/~incal
- Re: How do I pass a variable defined in a wrapping let, to a lambda?, (continued)
- Re: How do I pass a variable defined in a wrapping let, to a lambda?, Michael Heerdegen, 2022/03/11
- Re: How do I pass a variable defined in a wrapping let, to a lambda?, Eric Abrahamsen, 2022/03/11
- Re: How do I pass a variable defined in a wrapping let, to a lambda?, Emanuel Berg, 2022/03/11
- Re: How do I pass a variable defined in a wrapping let, to a lambda?, Jean Louis, 2022/03/12
- `let' vs `let*' (was: Re: How do I pass a variable defined in a wrapping let, to a lambda?), Emanuel Berg, 2022/03/14
- Re: `let' vs `let*' (was: Re: How do I pass a variable defined in a wrapping let, to a lambda?), Jean Louis, 2022/03/15
- Re: `let' vs `let*' (was: Re: How do I pass a variable defined in a wrapping let, to a lambda?),
Emanuel Berg <=
- RE: [External] : `let' vs `let*' (was: Re: How do I pass a variable defined in a wrapping let, to a lambda?), Drew Adams, 2022/03/15
- Re: [External] : `let' vs `let*' (was: Re: How do I pass a variable defined in a wrapping let, to a lambda?), tomas, 2022/03/15
- Re: [External] : `let' vs `let*', Stefan Monnier, 2022/03/15
- Re: [External] : `let' vs `let*' (was: Re: How do I pass a variable defined in a wrapping let, to a lambda?), Emanuel Berg, 2022/03/15
- Re: [External] : `let' vs `let*' (was: Re: How do I pass a variable defined in a wrapping let, to a lambda?), Emanuel Berg, 2022/03/15
- Re: How do I pass a variable defined in a wrapping let, to a lambda?, Emanuel Berg, 2022/03/14
Re: How do I pass a variable defined in a wrapping let, to a lambda?, Emanuel Berg, 2022/03/11