src/HOL/Finite_Set.thy
changeset 51546 2e26df807dc7
parent 51489 f738e6dbd844
child 51598 5dbe537087aa
     1.1 --- a/src/HOL/Finite_Set.thy	Tue Mar 26 20:55:21 2013 +0100
     1.2 +++ b/src/HOL/Finite_Set.thy	Tue Mar 26 21:53:56 2013 +0100
     1.3 @@ -1107,11 +1107,11 @@
     1.4  
     1.5  interpretation card!: folding "\<lambda>_. Suc" 0
     1.6  where
     1.7 -  "card.F = card"
     1.8 +  "folding.F (\<lambda>_. Suc) 0 = card"
     1.9  proof -
    1.10    show "folding (\<lambda>_. Suc)" by default rule
    1.11    then interpret card!: folding "\<lambda>_. Suc" 0 .
    1.12 -  show "card.F = card" by (simp only: card_def)
    1.13 +  from card_def show "folding.F (\<lambda>_. Suc) 0 = card" by rule
    1.14  qed
    1.15  
    1.16  lemma card_infinite: