1.1 --- a/doc-src/TutorialI/fp.tex Wed Aug 30 18:05:20 2000 +0200
1.2 +++ b/doc-src/TutorialI/fp.tex Wed Aug 30 18:09:20 2000 +0200
1.3 @@ -405,16 +405,12 @@
1.4
1.5 Simplification is one of the central theorem proving tools in Isabelle and
1.6 many other systems. The tool itself is called the \bfindex{simplifier}. The
1.7 -purpose of this section is twofold: to introduce the many features of the
1.8 -simplifier (\S\ref{sec:SimpFeatures}) and to explain a little bit how the
1.9 -simplifier works (\S\ref{sec:SimpHow}). Anybody intending to use HOL should
1.10 -read \S\ref{sec:SimpFeatures}, and the serious student should read
1.11 -\S\ref{sec:SimpHow} as well in order to understand what happened in case
1.12 -things do not simplify as expected.
1.13 -
1.14 -
1.15 -\subsection{Using the simplifier}
1.16 -\label{sec:SimpFeatures}
1.17 +purpose of this section is introduce the many features of the simplifier.
1.18 +Anybody intending to use HOL should read this section. Later on
1.19 +(\S\ref{sec:simplification-II}) we explain some more advanced features and a
1.20 +little bit of how the simplifier works. The serious student should read that
1.21 +section as well, in particular in order to understand what happened if things
1.22 +do not simplify as expected.
1.23
1.24 \subsubsection{What is simplification}
1.25
1.26 @@ -572,11 +568,11 @@
1.27 inductive proofs. The first one we have already mentioned in our initial
1.28 example:
1.29 \begin{quote}
1.30 -{\em 1. Theorems about recursive functions are proved by induction.}
1.31 +\emph{Theorems about recursive functions are proved by induction.}
1.32 \end{quote}
1.33 In case the function has more than one argument
1.34 \begin{quote}
1.35 -{\em 2. Do induction on argument number $i$ if the function is defined by
1.36 +\emph{Do induction on argument number $i$ if the function is defined by
1.37 recursion in argument number $i$.}
1.38 \end{quote}
1.39 When we look at the proof of {\makeatother\isa{(xs @ ys) @ zs = xs @ (ys @
1.40 @@ -598,8 +594,8 @@
1.41 side, the simpler \isa{rev} on the right-hand side. This constitutes
1.42 another, albeit weak heuristic that is not restricted to induction:
1.43 \begin{quote}
1.44 - {\em 5. The right-hand side of an equation should (in some sense) be
1.45 - simpler than the left-hand side.}
1.46 + \emph{The right-hand side of an equation should (in some sense) be simpler
1.47 + than the left-hand side.}
1.48 \end{quote}
1.49 The heuristic is tricky to apply because it is not obvious that
1.50 \isa{rev xs \at\ ys} is simpler than \isa{itrev xs ys}. But see what