Metamath Proof Explorer


Definition df-comf

Description: Define the functionalized composition operator, which is exactly like comp but is guaranteed to be a function of the proper type. (Contributed by Mario Carneiro, 4-Jan-2017)

Ref Expression
Assertion df-comf comp𝑓=cVxBasec×Basec,yBasecg2ndxHomcy,fHomcxgxcompcyf

Detailed syntax breakdown

Step Hyp Ref Expression
0 ccomf classcomp𝑓
1 vc setvarc
2 cvv classV
3 vx setvarx
4 cbs classBase
5 1 cv setvarc
6 5 4 cfv classBasec
7 6 6 cxp classBasec×Basec
8 vy setvary
9 vg setvarg
10 c2nd class2nd
11 3 cv setvarx
12 11 10 cfv class2ndx
13 chom classHom
14 5 13 cfv classHomc
15 8 cv setvary
16 12 15 14 co class2ndxHomcy
17 vf setvarf
18 11 14 cfv classHomcx
19 9 cv setvarg
20 cco classcomp
21 5 20 cfv classcompc
22 11 15 21 co classxcompcy
23 17 cv setvarf
24 19 23 22 co classgxcompcyf
25 9 17 16 18 24 cmpo classg2ndxHomcy,fHomcxgxcompcyf
26 3 8 7 6 25 cmpo classxBasec×Basec,yBasecg2ndxHomcy,fHomcxgxcompcyf
27 1 2 26 cmpt classcVxBasec×Basec,yBasecg2ndxHomcy,fHomcxgxcompcyf
28 0 27 wceq wffcomp𝑓=cVxBasec×Basec,yBasecg2ndxHomcy,fHomcxgxcompcyf