[Merged by Bors] - feat(order/filter/basic): add map_le_map and map_injective
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eric-wieser
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Jul 5, 2022
src/order/filter/basic.lean
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| lemma map_le_map {f g : filter α} {m : α → β} (hm : injective m) : map m f ≤ map m g ↔ f ≤ g := | ||
| by rw [map_le_iff_le_comap, comap_map hm] |
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Isn't this just a weaker version of the bizarrely-named le_of_map_le_map_inj_iff above?
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(which should probably be named map_le_map_iff_of_inj_on and be stated using set.inj_on)
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Renamed, removed -> versions in favor of iffs.
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@eric-wieser Could you please have another look?
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bors merge Thanks! |
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* Add `filter.map_le_map`, an `iff` version of `filter.map_mono`. * Add `filter.map_injective`, a `function.injective` version of `filter.map_inj`.
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Pull request successfully merged into master. Build succeeded: |
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map_le_map and map_injectivemap_le_map and map_injective
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filter.map_le_map, aniffversion offilter.map_mono.filter.map_injective, afunction.injectiveversion offilter.map_inj.