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-rw-r--r--Nominal/Support.lean10
1 files changed, 5 insertions, 5 deletions
diff --git a/Nominal/Support.lean b/Nominal/Support.lean
index efed617..78e8b3e 100644
--- a/Nominal/Support.lean
+++ b/Nominal/Support.lean
@@ -8,7 +8,7 @@ import Nominal.Helpers.Finset
This file provides basic definitions for support of (FPerm 𝔸)-sets and nominal sets.
-/
-variable (𝔸 : Type)
+variable (𝔸 : Type) [Infinite 𝔸] [Countable 𝔸] [DecidableEq 𝔸]
/-!
## Support Definitions
@@ -54,7 +54,7 @@ lemma support_superset {x : X} {S T : Set 𝔸} : HasSupport 𝔸 x S β†’ S βŠ†
exact hΟ€ a (hsub ha)
/-- For two finite supports, the intersection is also a support. -/
-lemma support_inter [Infinite 𝔸] {x : X} {S T : Set 𝔸} : HasSupport 𝔸 x S β†’ S.Finite β†’ HasSupport 𝔸 x T β†’ T.Finite β†’ HasSupport 𝔸 x (S ∩ T) := by
+lemma support_inter {x : X} {S T : Set 𝔸} : HasSupport 𝔸 x S β†’ S.Finite β†’ HasSupport 𝔸 x T β†’ T.Finite β†’ HasSupport 𝔸 x (S ∩ T) := by
intro h_S_support h_S_finite h_T_support h_T_finite Ο€ h_Ο€_fix
let Ο€' := Ο€.val
let h_Ο€_fin := Ο€.prop
@@ -151,7 +151,7 @@ lemma support_inter [Infinite 𝔸] {x : X} {S T : Set 𝔸} : HasSupport 𝔸 x
_ = x := by rw [h_T_support h_Οƒ_fixT]
/-- For a finite number of finite supports, the intersection is also a support. -/
-lemma support_sInter [Infinite 𝔸] {x : X} {C : Set (Set 𝔸)}: C.Finite β†’ C.Nonempty β†’ (βˆ€ S ∈ C, HasSupport 𝔸 x S ∧ S.Finite) β†’ HasSupport 𝔸 x (β‹‚β‚€ C) := by
+lemma support_sInter {x : X} {C : Set (Set 𝔸)}: C.Finite β†’ C.Nonempty β†’ (βˆ€ S ∈ C, HasSupport 𝔸 x S ∧ S.Finite) β†’ HasSupport 𝔸 x (β‹‚β‚€ C) := by
suffices (C : Finset (Set 𝔸)) : C.Nonempty β†’ (βˆ€ S ∈ C, HasSupport 𝔸 x S ∧ S.Finite) β†’ HasSupport 𝔸 x (β‹‚β‚€ C.toSet) ∧ (β‹‚β‚€ C.toSet).Finite
Β· intro hfin
rw [show C = hfin.toFinset.toSet by simp]
@@ -207,7 +207,7 @@ lemma supp_finite {x : X} : (supp 𝔸 x).Finite := by
exact Set.mem_sep hsuppS hfinS
/-- We can restrict the supp definition to subsets of a single finite support. -/
-private lemma supp_equiv_finite [Infinite 𝔸] {x : X} {S : Set 𝔸} : PermSet.HasSupport 𝔸 x S β†’ S.Finite β†’ supp 𝔸 x = β‹‚β‚€ { T : Set 𝔸 | T βŠ† S ∧ PermSet.HasSupport 𝔸 x T ∧ T.Finite } := by
+private lemma supp_equiv_finite {x : X} {S : Set 𝔸} : PermSet.HasSupport 𝔸 x S β†’ S.Finite β†’ supp 𝔸 x = β‹‚β‚€ { T : Set 𝔸 | T βŠ† S ∧ PermSet.HasSupport 𝔸 x T ∧ T.Finite } := by
intro hsuppS hfinS
unfold supp; ext a
constructor
@@ -223,7 +223,7 @@ private lemma supp_equiv_finite [Infinite 𝔸] {x : X} {S : Set 𝔸} : PermSet
Β· exact Set.Finite.inter_of_left hfinS T
/-- The least finite support is itself a support. -/
-lemma supp_is_support [Infinite 𝔸] {x : X} : PermSet.HasSupport 𝔸 x (supp 𝔸 x) := by
+lemma supp_is_support {x : X} : PermSet.HasSupport 𝔸 x (supp 𝔸 x) := by
obtain ⟨S, ⟨hsuppS, hfinS⟩⟩ := nom.fin_supp x
rw [supp_equiv_finite 𝔸 hsuppS hfinS]
apply PermSet.support_sInter