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Theorem topological_space.opens.union_eq

Modification history

2023-02-09 19:18
src/topology/sets/opens.lean
refactor(topology/sets/opens): use a `structure` for `opens` and `open_nhds_of` (#18409) …
Deleted topological_space.opens.union_eqView on Github →
2019-03-03 19:05
src/topology/basic.lean
chore(topology): Splits topology.basic and topology.continuity (#785) …
Modified topological_space.opens.union_eqView on Github →
2019-02-28 10:33
src/topology/basic.lean
feat(topology/basic): Add instances for subset/inter/union for opens(X) (#763) …
Added topological_space.opens.union_eqView on Github →