[Rd] Generalised piping into operators

[Dominick Samperi]

A few years ago there was a post by the author of pipeR suggesting improvements in efficiency and reliability. Is there collaboration between these various pipe projects?

Sent from my iPhone

> On Apr 21, 2023, at 1:01 PM, Duncan Murdoch <murdoch.duncan using gmail.com> wrote:
> 
> On 21/04/2023 12:16 p.m., Michael Milton wrote:
>> I'm afraid I don't understand. I know that parsing `+`(1, 1) returns a result equivalent to `1 + 1`, but why does that impose a restriction on parsing the pipe operator? What is the downside of allowing arbitrary RHS functions?
> 
> I thought the decision to exclude "_ + 1" happens after enough parsing has happened so that the code making the decision can't tell the difference between "_ + 1" and "`+`(_, 1)".  I might be wrong about that, but this suggests it:
> 
>  > quote(_ + 1)
>  Error in quote("_" + 1) : invalid use of pipe placeholder (<input>:1:0)
>  > quote(`+`(_,  1))
>  Error in quote("_" + 1) : invalid use of pipe placeholder (<input>:1:0)
> 
> On the other hand, this works:
> 
>  > quote(x |> `+`(e1 = _, 1))
>  x + 1
> 
> So maybe `+`() is fine after all.
> 
> Duncan Murdoch
> 
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