@derived functions appear to ignore keyword arguments

[mabokhamis]

@dervied Salsa functions appear to silently ignore their keyword arguments. Consider the following testcase:

using Salsa

rt = Runtime()

@declare_input x(rt)::Int

set_x!(rt, 0)

@derived function f(rt::Runtime; y::Int = 0)
    return x(rt) + y
end

println(f(rt; y = 2)) // This prints 0, as if the keyword argument `y = 2` was not provided

Perhaps if keyword arguments are not supported in Salsa, we should check for them and issue errors/warnings.