Derivative as a function

[Nikos Apostolakis <nea@diamond.boisestate.edu>, Thu, 21 Oct 2004 05:02:06 -0600]:
> Also is there a way to define a function whose argument is a function?

Does this do what you want?

,----
| (C93) foo(f,x) := f(x);
| 
| (D93)                          foo(f, x) := f(x)
| (C94) foo(sin,%pi);
| 
| (D94)                                  0
`----

HTH,

Albert.