Returns the number of input/output arguments in a function call
[lhs [,rhs] ]=argn()
lhs=argn(1)
rhs=argn(2)
This function is used inside a function definition. It gives the number of actual inputs arguments ( rhs) and output arguments ( lhs) passed to the function when the function is called. It is usually used in function definitions to deal with optional arguments.
function concat=myOwnFunction(name, optional)
[lhs,rhs]=argn(0)
if rhs <= 1 then
optional="my Optional value"
end
if rhs == 0 then
`error`_("Expect at least one argument")
end
concat=name+" "+optional
endfunction