Find functions with specific arguments

Question

How can you find the names and locations of all the functions that have a specific argument? Is there a way to find them for functions in the global environment, attached packa

Answer 1

I assume that you ask the question just to not lose Ben great answer. Here I slightly modify Ben answer to search for any argument :

uses_arg <- function(x,arg) 
  is.function(fx <- get(x)) && 
  arg %in% names(formals(fx))

For example to get function with na.rm argument :

basevals <- ls(pos="package:base")      ## package name : here I use the base package
basevals[sapply(basevals,uses_arg,'na.rm')]

EDIT

better to name argument of ls in conjunction with asNamespace :

basevals  <- ls(asNamespace('base'))
basevals[sapply(basevals,uses_arg,'na.rm')]