diff -r 4536782969fa -r c39f83d8daeb CookBook/Package/Ind_Examples.thy --- a/CookBook/Package/Ind_Examples.thy Sat Feb 14 16:09:04 2009 +0000 +++ b/CookBook/Package/Ind_Examples.thy Sun Feb 15 18:58:21 2009 +0000 @@ -5,8 +5,8 @@ section{* Examples of Inductive Definitions \label{sec:ind-examples} *} text {* - Let us first give three examples showing how to define by hand inductive - predicates and then also how to prove by hand characteristic properties + Let us first give three examples showing how to define inductive + predicates by hand and then also how to prove by hand characteristic properties about them, such as introduction rules and induction principles. From these examples, we will figure out a general method for defining inductive predicates. The aim in this section is \emph{not} to write proofs that are as @@ -66,7 +66,7 @@ text {* The proofs for the introduction are slightly more complicated. We need to prove the facs @{prop "trcl R x x"} and @{prop "R x y \ trcl R y z \ trcl R x z"}. - In order to prove the first goal, we again unfold the definition and + In order to prove the first fact, we again unfold the definition and then apply the introdution rules for @{text "\"} and @{text "\"} as often as possible. We then end up in the goal state: *} @@ -270,7 +270,7 @@ and the implication in the premise. We first convert the meta-level universal quantifier and implication to their object-level counterparts. Unfolding the definition of @{text accpart} and applying the introduction rules for @{text "\"} and @{text "\"} - yields the following proof state: + yields the following goal state: *} (*<*)lemma accpartI: "(\y. R y x \ accpart R y) \ accpart R x" @@ -280,7 +280,7 @@ (*<*)oops(*>*) text {* - Applying the second assumption produces a proof state with the new local assumption + Applying the second assumption produces a goal state with the new local assumption @{term "R y x"}, which will then be used to solve the goal @{term "P y"} using the first assumption. *}