Metamath Proof Explorer


Definition df-topon

Description: Define the function that associates with a set the set of topologies on it. (Contributed by Stefan O'Rear, 31-Jan-2015)

Ref Expression
Assertion df-topon TopOn = b V j Top | b = j

Detailed syntax breakdown

Step Hyp Ref Expression
0 ctopon class TopOn
1 vb setvar b
2 cvv class V
3 vj setvar j
4 ctop class Top
5 1 cv setvar b
6 3 cv setvar j
7 6 cuni class j
8 5 7 wceq wff b = j
9 8 3 4 crab class j Top | b = j
10 1 2 9 cmpt class b V j Top | b = j
11 0 10 wceq wff TopOn = b V j Top | b = j