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Theorem is_open_union

Modification history

2021-05-19 12:41
src/topology/basic.lean
refactor(topology/basic): use dot notation in `is_open.union` and friends (#7647) …
Deleted is_open_unionView on Github →
2017-08-10 16:41
topology/topological_space.lean
rename open -> is_open, closed -> is_closed
Added is_open_unionView on Github →