[R] passing elements of named vector / named list to function

[Rainer M Krug]

Hi

Following scenario: I have a function fun

--8<---------------cut here---------------start------------->8---
fun <- function(A, B, C, ...){paste(A, B, C, ...)}
--8<---------------cut here---------------end--------------->8---

and x defined as follow

--8<---------------cut here---------------start------------->8---
x <- 1:5
names(x) <- LETTERS[x]
--8<---------------cut here---------------end--------------->8---

now I want to pass the *elements* of x to fun as named arguments, i.e.

,----
| > fun(A=1, B=2, C=3, D=4, E=5)
| [1] "1 2 3 4 5"
`----

The below examples obviously do not work:

,----
| > fun(x)
| Error in paste(A, B, C, list(...)) :
|   argument "B" is missing, with no default
| > fun(unlist(x))
| Error in paste(A, B, C, list(...)) :
|   argument "B" is missing, with no default
`----

How can I extract from x the elements and pass them on to fun()?

I could easily change x to a list() if this would be easier.

--8<---------------cut here---------------start------------->8---
x <- list(A=1, B=2, C=3, D=4, E=5)
--8<---------------cut here---------------end--------------->8---

In my actual program, x can have different elements as well as fun -
this is decided programmatically.

Any suggestions how I can achieve this?

Thanks,

Rainer

-- 
Rainer M. Krug
email: Rainer<at>krugs<dot>de
PGP: 0x0F52F982
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