Description: Functionality of a class given by a maps-to notation. (Contributed by FL, 17-Feb-2008) (Revised by Mario Carneiro, 31-May-2014)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | funmpt2.1 | |- F = ( x e. A |-> B ) |
|
| Assertion | funmpt2 | |- Fun F |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | funmpt2.1 | |- F = ( x e. A |-> B ) |
|
| 2 | funmpt | |- Fun ( x e. A |-> B ) |
|
| 3 | 1 | funeqi | |- ( Fun F <-> Fun ( x e. A |-> B ) ) |
| 4 | 2 3 | mpbir | |- Fun F |