From ggrothend|eck @end|ng |rom gm@||@com  Mon Dec  7 19:31:35 2020
From: ggrothend|eck @end|ng |rom gm@||@com (Gabor Grothendieck)
Date: Mon, 7 Dec 2020 13:31:35 -0500
Subject: [Rd] New pipe operator
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On Mon, Dec 7, 2020 at 12:54 PM Duncan Murdoch <murdoch.duncan at gmail.com> wrote:
> An advantage of the current implementation is that it's simple and easy
> to understand.  Once you make it a user-modifiable binary operator,
> things will go kind of nuts.
>
> For example, I doubt if there are many users of magrittr's pipe who
> really understand its subtleties, e.g. the example in Luke's paper where
> 1 %>% c(., 2) gives c(1,2), but 1 %>% c(c(.), 2) gives c(1, 1, 2). (And
> I could add 1 %>% c(c(.), 2, .) and  1 %>% c(c(.), 2, . + 2)  to
> continue the fun.)

The rule is not so complicated.  Automatic insertion is done unless
you use dot in the top level function or if you surround it with
{...}.  It really makes sense since if you use gsub(pattern,
replacement, .) then surely you don't want automatic insertion and if
you surround it with { ... } then you are explicitly telling it not
to.

Assuming the existence of placeholders a possible simplification would
be to NOT do automatic insertion if { ... } is used and to use it
otherwise although personally having used it for some time I find the
existing rule in magrittr generally does what you want.



[Rd] New pipe operator
Gabor Grothendieck