src/HOL/Statespace/DistinctTreeProver.thy
changeset 29291 d3cc5398bad5
parent 29269 5c25a2012975
child 32010 cb1a1c94b4cd
     1.1 --- a/src/HOL/Statespace/DistinctTreeProver.thy	Thu Jan 01 14:23:39 2009 +0100
     1.2 +++ b/src/HOL/Statespace/DistinctTreeProver.thy	Thu Jan 01 17:47:12 2009 +0100
     1.3 @@ -452,7 +452,7 @@
     1.4    case Tip thus ?case by simp
     1.5  next
     1.6    case (Node l x d r)
     1.7 -  have sub: "subtract (Node l x d r) t\<^isub>2 = Some t".
     1.8 +  have sub: "subtract (Node l x d r) t\<^isub>2 = Some t" by fact
     1.9    show ?case
    1.10    proof (cases "delete x t\<^isub>2")
    1.11      case (Some t\<^isub>2')