
diff -r 02c51ca9c531 -r d17c0b34d5c8 doc-src/TutorialI/Misc/document/pairs.tex
--- a/doc-src/TutorialI/Misc/document/pairs.tex	Fri Aug 04 23:02:11 2000 +0200
+++ b/doc-src/TutorialI/Misc/document/pairs.tex	Sun Aug 06 15:26:53 2000 +0200
@@ -1,5 +1,25 @@
 \begin{isabelle}%
-~{"}let~(x,y)~=~f~z~in~(y,x){"}~{"}case~xs~of~[]~{\isasymRightarrow}~0~|~(x,y)\#zs~{\isasymRightarrow}~x+y{"}\isanewline
+%
+\begin{isamarkuptext}%
+HOL also has pairs: \isa{($a@1$,$a@2$)} is of type \isa{$\tau@1$ *
+  $\tau@2$} provided each $a@i$ is of type $\tau@i$. The components of a pair
+are extracted by \isa{fst} and \isa{snd}: \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
+\isa{$\tau@1$ * $\tau@2$ * $\tau@3$} for \isa{$\tau@1$ * ($\tau@2$ *
+  $\tau@3$)}. Therefore we have \isa{fst(snd($a@1$,$a@2$,$a@3$)) = $a@2$}.
+
+It is possible to use (nested) tuples as patterns in abstractions, for
+example \isa{\isasymlambda(x,y,z).x+y+z} and
+\isa{\isasymlambda((x,y),z).x+y+z}.
+In addition to explicit $\lambda$-abstractions, tuple patterns can be used in
+most variable binding constructs. Typical examples are
+\begin{quote}
+\isa{let\ (x,\ y)\ =\ f\ z\ in\ (y,\ x)}\\
+\isa{case\ xs\ of\ []\ {\isasymRightarrow}\ 0\ |\ (x,\ y)\ \#\ zs\ {\isasymRightarrow}\ x\ +\ y}
+\end{quote}
+Further important examples are quantifiers and sets (see~\S\ref{quant-pats}).%
+\end{isamarkuptext}%
 \end{isabelle}%
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