DoCall("complex", list(imaginary = 1:3))
## if we already have a list (e.g. a data frame)
## we need c() to add further arguments
tmp <- expand.grid(letters[1:2], 1:3, c("+", "-"))
DoCall("paste", c(tmp, sep = ""))
## examples of where objects will be found.
A <- 2
f <- function(x) print(x^2)
env <- new.env()
assign("A", 10, envir = env)
assign("f", f, envir = env)
f <- function(x) print(x)
f(A) # 2
DoCall("f", list(A)) # 2
DoCall("f", list(A), envir = env) # 4
DoCall(f, list(A), envir = env) # 2
DoCall("f", list(quote(A)), envir = env) # 100
DoCall(f, list(quote(A)), envir = env) # 10
DoCall("f", list(as.name("A")), envir = env) # 100
eval(call("f", A)) # 2
eval(call("f", quote(A))) # 2
eval(call("f", A), envir = env) # 4
eval(call("f", quote(A)), envir = env) # 100
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