--- a/doc-src/TutorialI/Misc/pairs2.thy Tue Aug 28 18:46:15 2012 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,35 +0,0 @@
-(*<*)
-theory pairs2 imports Main begin;
-(*>*)
-text{*\label{sec:pairs}\index{pairs and tuples}
-HOL also has ordered pairs: \isa{($a@1$,$a@2$)} is of type $\tau@1$
-\indexboldpos{\isasymtimes}{$Isatype} $\tau@2$ provided each $a@i$ is of type
-$\tau@i$. The functions \cdx{fst} and
-\cdx{snd} extract the components of a pair:
- \isa{fst($x$,$y$) = $x$} and \isa{snd($x$,$y$) = $y$}. Tuples
-are simulated by pairs nested to the right: \isa{($a@1$,$a@2$,$a@3$)} stands
-for \isa{($a@1$,($a@2$,$a@3$))} and $\tau@1 \times \tau@2 \times \tau@3$ for
-$\tau@1 \times (\tau@2 \times \tau@3)$. Therefore we have
-\isa{fst(snd($a@1$,$a@2$,$a@3$)) = $a@2$}.
-
-Remarks:
-\begin{itemize}
-\item
-There is also the type \tydx{unit}, which contains exactly one
-element denoted by~\cdx{()}. This type can be viewed
-as a degenerate product with 0 components.
-\item
-Products, like type @{typ nat}, are datatypes, which means
-in particular that @{text induct_tac} and @{text case_tac} are applicable to
-terms of product type.
-Both split the term into a number of variables corresponding to the tuple structure
-(up to 7 components).
-\item
-Tuples with more than two or three components become unwieldy;
-records are preferable.
-\end{itemize}
-For more information on pairs and records see Chapter~\ref{ch:more-types}.
-*}
-(*<*)
-end
-(*>*)