tst <- function(a, b = 3, ...) {nargs()}
tst() # 0
tst(clicketyclack) # 1 (even non-existing)
tst(c1, a2, rr3) # 3
foo <- function(x, y, z, w) {
cat("call was ", deparse(match.call()), "\n", sep = "")
nargs()
}
foo() # 0
foo(, , 3) # 3
foo(z = 3) # 1, even though this is the same call
nargs() # not really meaningful
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