This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Define the composition of two functors. (Contributed by Mario Carneiro, 3-Jan-2017)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-cofu | |- o.func = ( g e. _V , f e. _V |-> <. ( ( 1st ` g ) o. ( 1st ` f ) ) , ( x e. dom dom ( 2nd ` f ) , y e. dom dom ( 2nd ` f ) |-> ( ( ( ( 1st ` f ) ` x ) ( 2nd ` g ) ( ( 1st ` f ) ` y ) ) o. ( x ( 2nd ` f ) y ) ) ) >. ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | ccofu | |- o.func |
|
| 1 | vg | |- g |
|
| 2 | cvv | |- _V |
|
| 3 | vf | |- f |
|
| 4 | c1st | |- 1st |
|
| 5 | 1 | cv | |- g |
| 6 | 5 4 | cfv | |- ( 1st ` g ) |
| 7 | 3 | cv | |- f |
| 8 | 7 4 | cfv | |- ( 1st ` f ) |
| 9 | 6 8 | ccom | |- ( ( 1st ` g ) o. ( 1st ` f ) ) |
| 10 | vx | |- x |
|
| 11 | c2nd | |- 2nd |
|
| 12 | 7 11 | cfv | |- ( 2nd ` f ) |
| 13 | 12 | cdm | |- dom ( 2nd ` f ) |
| 14 | 13 | cdm | |- dom dom ( 2nd ` f ) |
| 15 | vy | |- y |
|
| 16 | 10 | cv | |- x |
| 17 | 16 8 | cfv | |- ( ( 1st ` f ) ` x ) |
| 18 | 5 11 | cfv | |- ( 2nd ` g ) |
| 19 | 15 | cv | |- y |
| 20 | 19 8 | cfv | |- ( ( 1st ` f ) ` y ) |
| 21 | 17 20 18 | co | |- ( ( ( 1st ` f ) ` x ) ( 2nd ` g ) ( ( 1st ` f ) ` y ) ) |
| 22 | 16 19 12 | co | |- ( x ( 2nd ` f ) y ) |
| 23 | 21 22 | ccom | |- ( ( ( ( 1st ` f ) ` x ) ( 2nd ` g ) ( ( 1st ` f ) ` y ) ) o. ( x ( 2nd ` f ) y ) ) |
| 24 | 10 15 14 14 23 | cmpo | |- ( x e. dom dom ( 2nd ` f ) , y e. dom dom ( 2nd ` f ) |-> ( ( ( ( 1st ` f ) ` x ) ( 2nd ` g ) ( ( 1st ` f ) ` y ) ) o. ( x ( 2nd ` f ) y ) ) ) |
| 25 | 9 24 | cop | |- <. ( ( 1st ` g ) o. ( 1st ` f ) ) , ( x e. dom dom ( 2nd ` f ) , y e. dom dom ( 2nd ` f ) |-> ( ( ( ( 1st ` f ) ` x ) ( 2nd ` g ) ( ( 1st ` f ) ` y ) ) o. ( x ( 2nd ` f ) y ) ) ) >. |
| 26 | 1 3 2 2 25 | cmpo | |- ( g e. _V , f e. _V |-> <. ( ( 1st ` g ) o. ( 1st ` f ) ) , ( x e. dom dom ( 2nd ` f ) , y e. dom dom ( 2nd ` f ) |-> ( ( ( ( 1st ` f ) ` x ) ( 2nd ` g ) ( ( 1st ` f ) ` y ) ) o. ( x ( 2nd ` f ) y ) ) ) >. ) |
| 27 | 0 26 | wceq | |- o.func = ( g e. _V , f e. _V |-> <. ( ( 1st ` g ) o. ( 1st ` f ) ) , ( x e. dom dom ( 2nd ` f ) , y e. dom dom ( 2nd ` f ) |-> ( ( ( ( 1st ` f ) ` x ) ( 2nd ` g ) ( ( 1st ` f ) ` y ) ) o. ( x ( 2nd ` f ) y ) ) ) >. ) |