`field_type_ff'
---------------

field_type_ff()
     :: Type of the current base field.

RETURN
     integer

   * Returns the type of the current base field.

   * If no field is set, 0 is returned. If GF(p) is set, 1 is returned.
     If GF(2^n) is set, 2 is returned.

     [0] field_type_ff();
     0
     [1] setmod_ff(3);
     3
     [2] field_type_ff();
     1
     [3] setmod_ff(x^2+x+1);
     x^2+x+1
     [4] field_type_ff();
     2

References
     *Note `setmod_ff': setmod_ff

