fixed def/lemma

leanprover-community · Feb 13, 2025 · f7edaaf · f7edaaf
1 parent ff381c2
commit f7edaaf
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/Mathlib/SetTheory/Cardinal/Cofinality.lean b/Mathlib/SetTheory/Cardinal/Cofinality.lean
@@ -920,7 +920,7 @@ theorem isRegular_cof {o : Ordinal} (h : o.IsLimit) : IsRegular o.cof :=
   ⟨aleph0_le_cof.2 h, (cof_cof o).ge⟩
 
 /-- If `c` is a regular cardinal, then `c.ord.toType` has a least element. -/
-noncomputable def IsRegular.ne_zero {c : Cardinal} (H : c.IsRegular) : c ≠ 0 :=
+lemma IsRegular.ne_zero {c : Cardinal} (H : c.IsRegular) : c ≠ 0 :=
   H.pos.ne.symm
 
 theorem isRegular_aleph0 : IsRegular ℵ₀ :=