Mathematica: Expression with function calls to list of arguments

Question

I have an expression like this:

expr=F[0, 1] + 2 F[0, 0] - 17*F[2, 0]

and i want to transform it to a list consisting of all function calls with its arguments:

MyList={F[0, 1], F[0, 0], F[2, 0]}

Does anyone know a clever way to do this in Mathematica?

My currently best solution is using ToString and do string-manipulations, but it is defintivly very slow and ugly.

Thanks alot! Andreas

Answer 1

 Cases[ expr , F[__] , Infinity]

{F[0, 0], F[0, 1], F[2, 0]}

Note the order you keyed them in is lost because mathematica puts the terms in canonical order as soon as you evaluate the expr=.. assignment.