The table on the right shows the complete assignment compatibilities for class types and class-wide types.
T and E are type classes.
The colors show the different assignment compatibilities:
| definite | the assignment is always possible |
| potential | the assignment can be possible, depending on the actual type of the expression |
| incompatible | the assignment is never possible |
| expression type | ||
|---|---|---|
| target type | E | E'CLASS |
| T | T equal E | |
| E ancestor of T or equal | ||
| T not equal E | T ancestor of E or not related | |
| T'CLASS | T ancestor of E or equal | T ancestor of E or equal |
| E ancestor of T | ||
| E ancestor of T or not related | E and T not related | |