author nipkow Tue, 18 Mar 2003 17:54:27 +0100 changeset 13868 01b516b64233 parent 13867 1fdecd15437f child 13869 18112403c809
*** empty log message ***
 NEWS file | annotate | diff | comparison | revisions doc-src/TutorialI/ToyList/ToyList.thy file | annotate | diff | comparison | revisions
--- a/NEWS	Mon Mar 17 18:38:50 2003 +0100
+++ b/NEWS	Tue Mar 18 17:54:27 2003 +0100
@@ -46,8 +46,8 @@

- Accepts free variables as head terms in congruence rules.  Useful in Isar.

-* Pure: New flag for triggering if the overall goal of a proof state should
-be printed:
+* Pure: The main goal of the proof state is no longer shown by default, only
+the subgoals. This behaviour is controlled by a new flag.
PG menu: Isabelle/Isar -> Settings -> Show Main Goal
(ML: Proof.show_main_goal).

--- a/doc-src/TutorialI/ToyList/ToyList.thy	Mon Mar 17 18:38:50 2003 +0100
+++ b/doc-src/TutorialI/ToyList/ToyList.thy	Tue Mar 18 17:54:27 2003 +0100
@@ -144,23 +144,21 @@
The name and the simplification attribute are optional.
Isabelle's response is to print the initial proof state consisting
of some header information (like how many subgoals there are) followed by
-@{goals[display,indent=0]}
+@{subgoals[display,indent=0]}
For compactness reasons we omit the header in this tutorial.
Until we have finished a proof, the \rmindex{proof state} proper
always looks like this:
\begin{isabelle}
-$G$\isanewline
~1.~$G\sb{1}$\isanewline
~~\vdots~~\isanewline
~$n$.~$G\sb{n}$
\end{isabelle}
-where $G$
-is the overall goal that we are trying to prove, and the numbered lines
-contain the subgoals $G\sb{1}$, \dots, $G\sb{n}$ that we need to prove to
-establish $G$.\index{subgoals}
-Initially there is only one subgoal, which is
-identical with the overall goal.  Normally $G$ is constant and only serves as
-a reminder. Hence we rarely show it in this tutorial.
+The numbered lines contain the subgoals $G\sb{1}$, \dots, $G\sb{n}$
+that we need to prove to establish the main goal.\index{subgoals}
+Initially there is only one subgoal, which is identical with the
+main goal. (If you always want to see the main goal as well,
+set the flag \isa{Proof.show_main_goal}\index{*show_main_goal (flag)}
+--- this flag used to be set by default.)

Let us now get back to @{prop"rev(rev xs) = xs"}. Properties of recursively
defined functions are best established by induction. In this case there is