From c@@rd|@g@bor @end|ng |rom gm@||@com  Mon Apr 13 09:51:16 2020
From: c@@rd|@g@bor @end|ng |rom gm@||@com (=?UTF-8?B?R8OhYm9yIENzw6FyZGk=?=)
Date: Mon, 13 Apr 2020 08:51:16 +0100
Subject: [Rd] detect ->
In-Reply-To: <6DB118E2-8C9A-4C5D-BC82-12B689C872FF@gmail.com>
References: <6DB118E2-8C9A-4C5D-BC82-12B689C872FF@gmail.com>
Message-ID: <CABtg=KmifDz6DbufPoBX0j4Suepm3pG6K=6PoPHJ4cCXAVYafg@mail.gmail.com>

That parser already flips -> to <- before creating the parse tree.

Gabor

On Mon, Apr 13, 2020 at 8:39 AM Adrian Du?a <dusa.adrian at gmail.com> wrote:
>
> I searched and tried for hours, to no avail although it looks simple.
>
> (function(x) substitute(x))(A <- B)
> #A <- B
>
> (function(x) substitute(x))(A -> B)
> # B <- A
>
> In the first example, A occurs on the LHS, but in the second example A is somehow evaluated as if it occured on the RHS, despite my understanding that substitute() returns the unevaluated parse tree.
>
> Is there any way, or is it even possible to detect the right hand assignment, to determine whether A occurs on the LHS?
>
> Thanks in advance for any hint,
> Adrian
>
> ?
> Adrian Dusa
> University of Bucharest
> Romanian Social Data Archive
> Soseaua Panduri nr. 90-92
> 050663 Bucharest sector 5
> Romania
> https://adriandusa.eu
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel



[Rd] detect ->
=?UTF-8?B?R8OhYm9yIENzw6FyZGk=?=