src/HOL/Induct/README.html
author paulson
Tue, 01 Sep 1998 15:04:59 +0200
changeset 5417 1f533238b53b
parent 3122 2fe26ca380a1
child 11053 026007eb2ccc
permissions -rw-r--r--
new theory Induct/FoldSet

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<H2>Induct--Examples of (Co)Inductive Definitions</H2>

<P>This directory is a collection of small examples to demonstrate
Isabelle/HOL's (co)inductive definitions package.  Large examples appear on
many other directories, such as Auth, IMP and Lambda.

<UL>
<LI><KBD>Perm</KBD> is a simple theory of permutations of lists.

<LI><KBD>FoldSet</KBD> declares a <EM>fold</EM> functional for finite sets.
Let f be an associative-commutative function with identity e.
For n non-negative we have
<PRE>
fold f e {x1,...,xn} = f x1 (... (f xn e))
</PRE>

<LI><KBD>Comb</KBD> proves the Church-Rosser theorem for combinators (<A
HREF="http://www.cl.cam.ac.uk/ftp/papers/reports/TR396-lcp-generic-automatic-proof-tools.ps.gz">paper
available</A>).

<LI><KBD>Mutil</KBD> is the famous Mutilated Chess Board problem (<A
HREF="http://www.cl.cam.ac.uk/ftp/papers/reports/TR394-lcp-mutilated-chess-board.dvi.gz">paper
available</A>).

<LI><KBD>PropLog</KBD> proves the completeness of a formalization of
propositional logic (<A
HREF="http://www.cl.cam.ac.uk/Research/Reports/TR312-lcp-set-II.ps.gz">paper
available</A>).

<LI><KBD>LFilter</KBD> is an inductive/corecursive formalization of the
<EM>filter</EM> functional for infinite streams.

<LI><KBD>Exp</KBD> demonstrates the use of iterated inductive definitions to
reason about mutually recursive relations.
</UL>

<HR>
<P>Last modified 7 May 1997

<ADDRESS>
<A NAME="lcp@cl.cam.ac.uk" HREF="mailto:lcp@cl.cam.ac.uk">lcp@cl.cam.ac.uk</A>
</ADDRESS>
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