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Re: Calling a function with undefined symbol
From: |
Michael Heerdegen |
Subject: |
Re: Calling a function with undefined symbol |
Date: |
Wed, 09 Nov 2022 16:59:01 +0100 |
User-agent: |
Gnus/5.13 (Gnus v5.13) |
Sam Steingold <sds@gnu.org> writes:
> > * Michael Heerdegen <zvpunry_urreqrtra@jro.qr> [2022-11-09 00:53:33
> > +0100]:
> >
> > Sam Steingold <sds@gnu.org> writes:
> >
> >> ((lambda (x) `(,x ',x)) (lambda (x) `(,x ',x)))
> >
> > (#1=(lambda (x) '(#1# '#1#)) #1#)
>
> Nah, (#1=(lambda (x) `(,x ',x)) #1#)
Yes, I was wrong two times: the first time when I posted the wrong
counterpart of the quote-quine. My version without quoting was a
slightly different thing because evaluation didn't stop. Your version
fits better.
And (lambda (x) '(#1# '#1#)) is nonsense because it ignores the
argument.
But why not ((lambda (x) `(,x ,x)) (lambda (x) `(,x ,x))) - why do you
quote the second list element? I guess you want to avoid that the
lambda is evaluated and gets a closure, but then you want
((lambda (x) `(,x ',x)) '(lambda (x) `(,x ',x)))
^
> I would rather avoid circular lists _in code_.
I had been wondering about the question: If
((lambda (x) `(,x ',x)) (lambda (x) `(,x ',x)))
is the version for n=1 arguments, how would a version for n=0 look like?
Then you could either construct (a) an expression that returns the n=0
counterpart, which is easy, or give (b) an expression that is the
counterpart itself. Then I think you need circular code because the
function does not receive an argument:
(#1=(lambda () '(#1#)))
Michael.
- Re: Calling a function with undefined symbol, (continued)
- Re: Calling a function with undefined symbol, Michael Heerdegen, 2022/11/07
- RE: [External] : Re: Calling a function with undefined symbol, Drew Adams, 2022/11/07
- Re: Calling a function with undefined symbol, Emanuel Berg, 2022/11/08
- Re: Calling a function with undefined symbol, Michael Heerdegen, 2022/11/08
- Re: Calling a function with undefined symbol, tomas, 2022/11/08
- Re: Calling a function with undefined symbol, Michael Heerdegen, 2022/11/08
- Re: Calling a function with undefined symbol, tomas, 2022/11/08
- Re: Calling a function with undefined symbol, Sam Steingold, 2022/11/08
- Re: Calling a function with undefined symbol, Michael Heerdegen, 2022/11/08
- Re: Calling a function with undefined symbol, Sam Steingold, 2022/11/09
- Re: Calling a function with undefined symbol,
Michael Heerdegen <=
- Re: Calling a function with undefined symbol, Emanuel Berg, 2022/11/16
- RE: [External] : Re: Calling a function with undefined symbol, Drew Adams, 2022/11/16
- Re: [External] : Re: Calling a function with undefined symbol, Emanuel Berg, 2022/11/18
- Re: Calling a function with undefined symbol, Michael Heerdegen, 2022/11/04
- Re: Calling a function with undefined symbol, Emanuel Berg, 2022/11/05