doc-src/TutorialI/Misc/document/prime_def.tex
changeset 11456 7eb63f63e6c6
parent 10267 325ead6d9457
child 11457 279da0358aa9
--- a/doc-src/TutorialI/Misc/document/prime_def.tex	Wed Jul 25 18:21:01 2001 +0200
+++ b/doc-src/TutorialI/Misc/document/prime_def.tex	Thu Jul 26 16:43:02 2001 +0200
@@ -5,14 +5,14 @@
 \begin{isamarkuptext}%
 \begin{warn}
 A common mistake when writing definitions is to introduce extra free
-variables on the right-hand side as in the following fictitious definition:
+variables on the right-hand side.  Consider the following, flawed definition
+(where \isa{dvd} means ``divides''):
 \begin{isabelle}%
 \ \ \ \ \ {\isachardoublequote}prime\ p\ {\isasymequiv}\ {\isadigit{1}}\ {\isacharless}\ p\ {\isasymand}\ {\isacharparenleft}m\ dvd\ p\ {\isasymlongrightarrow}\ m\ {\isacharequal}\ {\isadigit{1}}\ {\isasymor}\ m\ {\isacharequal}\ p{\isacharparenright}{\isachardoublequote}%
 \end{isabelle}
-where \isa{dvd} means ``divides''.
 Isabelle rejects this ``definition'' because of the extra \isa{m} on the
-right-hand side, which would introduce an inconsistency (why?). What you
-should have written is
+right-hand side, which would introduce an inconsistency (why?). 
+The correct version is
 \begin{isabelle}%
 \ \ \ \ \ {\isachardoublequote}prime\ p\ {\isasymequiv}\ {\isadigit{1}}\ {\isacharless}\ p\ {\isasymand}\ {\isacharparenleft}{\isasymforall}m{\isachardot}\ m\ dvd\ p\ {\isasymlongrightarrow}\ m\ {\isacharequal}\ {\isadigit{1}}\ {\isasymor}\ m\ {\isacharequal}\ p{\isacharparenright}{\isachardoublequote}%
 \end{isabelle}