--- a/src/HOL/Analysis/Continuum_Not_Denumerable.thy Sun Feb 05 20:09:39 2023 +0100
+++ b/src/HOL/Analysis/Continuum_Not_Denumerable.thy Mon Feb 06 15:41:23 2023 +0000
@@ -176,9 +176,7 @@
qed
lemma uncountable_closed_interval: "uncountable {a..b} \<longleftrightarrow> a < b" for a b :: real
- apply (rule iffI)
- apply (metis atLeastAtMost_singleton atLeastatMost_empty countable_finite finite.emptyI finite_insert linorder_neqE_linordered_idom)
- using real_interval_avoid_countable_set by fastforce
+ using infinite_Icc_iff by (fastforce dest: countable_finite real_interval_avoid_countable_set)
lemma open_minus_countable:
fixes S A :: "real set"