Derived Type Constructors.

Prism does not support constructors for derived types.

type point3 
  integer x,y,z;end 
type point3
type(point3) :: var,var2;

Prism does support assignment to derived types, however. For example:

(prism) assign var = var2

Although Fortran 90 allows the use of constructors, Prism does not support them. The following example is not supported:

(prism) assign var = point3(1,2,3)