R help - Sep 2004 - Getting the argument list within a function

Is there a way of getting the argument list of a function from within 
that function?  For example, something like

f <- function(x, y = 3) {
	fargs <- getFunctionArgList()
	print(fargs)  ## Should be `alist(x, y = 3)'
}

Thanks,

-roger

> Is there a way of getting the argument list of a function from within 
> that function?  For example, something like
Would formals() work for you here?

Is formals() what you're looking for?

Andy
> From: Roger D. Peng
> 
> Is there a way of getting the argument list of a function from within 
> that function?  For example, something like
> 
> f <- function(x, y = 3) {
> 	fargs <- getFunctionArgList()
> 	print(fargs)  ## Should be `alist(x, y = 3)'
> }
> 
> Thanks,
> 
> -roger
> 
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>

"Roger D. Peng" <rpeng at jhsph.edu> writes:
> Is there a way of getting the argument list of a function from within
> that function?  For example, something like
> 
> f <- function(x, y = 3) {
> 	fargs <- getFunctionArgList()
> 	print(fargs)  ## Should be `alist(x, y = 3)'
> }
> f
function(x, y = 3) {
  fargs <- formals(sys.function())
  print(fargs)  ## Should be equivalent to `alist(x=, y = 3)'
}

(Notice a couple of fine points...)

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   O__  ---- Peter Dalgaard             Blegdamsvej 3  
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