summaryrefslogtreecommitdiff
path: root/Nominal/Instances/Basic.lean
diff options
context:
space:
mode:
authorHannes Schulze <haschu0103@outlook.de>2025-11-20 11:56:18 +0100
committerHannes Schulze <haschu0103@outlook.de>2025-11-20 11:56:18 +0100
commitea38ef0cb2c57e10696c7fb6108732a6f454818c (patch)
tree512b528ce86c39fb29d66441af10b98d3318afe2 /Nominal/Instances/Basic.lean
parent80b248c5be656dd2b3ba753871aeeb7102e92ff8 (diff)
wip terms
Diffstat (limited to 'Nominal/Instances/Basic.lean')
-rw-r--r--Nominal/Instances/Basic.lean5
1 files changed, 5 insertions, 0 deletions
diff --git a/Nominal/Instances/Basic.lean b/Nominal/Instances/Basic.lean
index d41e87f..dea5bcf 100644
--- a/Nominal/Instances/Basic.lean
+++ b/Nominal/Instances/Basic.lean
@@ -282,6 +282,11 @@ lemma supp {x : X} : NominalSet.supp 𝔸 (Quotient.mk setoid.toSetoid x) = {a |
simp only [FPerm.swap_inv, PermSet.atom_swap, Equiv.swap_apply_left]
exact hc.right
+/-- If an atom is not in the support of the equivalence class, one can always pick a representative where it is not in the least support. -/
+lemma supp_pick_fresh {a : 𝔸} {x : X} : a ∉ NominalSet.supp 𝔸 (Quotient.mk setoid.toSetoid x) → ∃ (y : X), y ≈ x ∧ a ∉ NominalSet.supp 𝔸 y := by
+ contrapose
+ simp [not_exists, not_and, not_not, supp]
+
end Quotient
end Quotient