From 408c53f5dbffa0ab147ddbff1ee2f85a57382474 Mon Sep 17 00:00:00 2001
From: Camil Staps
Date: Sat, 24 Sep 2016 14:19:08 +0200
Subject: Removed strictness paragraph from docs; doesn't apply anymore
---
doc/examples.tex | 49 -------------------------------------------------
1 file changed, 49 deletions(-)
diff --git a/doc/examples.tex b/doc/examples.tex
index 421217c..7cffda5 100644
--- a/doc/examples.tex
+++ b/doc/examples.tex
@@ -66,52 +66,3 @@ subtraction. Hence, the example is rewritten as:
A complete overview of the \fuspel{code} names can be found in
\autoref{sec:code}.
-
-\subsection{Strictness}
-\label{sec:examples:strictness}
-
-By default, expressions are rewritten using the leftmost outermost rewriting
-strategy. This is guaranteed to find a normal form if one exists, but can be
-inefficient as it can lead to duplicate calculation. Consider the following
-example:
-
-\begin{lstlisting}
- mul x y = code mul x y;
- double x = (x, x);
- main = double (mul 5 10);
-\end{lstlisting}
-
-The result is \fuspel{(50,50)}. The expression is rewritten to \fuspel{(mul 5
-10, mul 5 10)}, and only then the \fuspel{mul} calls are rewritten. This is
-inefficient, because we have to multiply the numbers twice.
-
-We can force another rewriting strategy by adding a strictness annotation
-(\fuspel{!}) to the argument of \fuspel{double}:
-
-\begin{lstlisting}
- mul x y = code mul x y;
- double !x = (x, x);
- main = double (mul 5 10);
-\end{lstlisting}
-
-The result is the same, but the multiplication is only executed once. To apply
-the \fuspel{double} rule, its argument must be fully evaluated due to the
-strictness annotation. Therefore, the expression is first rewritten to
-\fuspel{double 50}.
-
-One must be careful with adding strictness annotations. Consider the following
-program:
-
-\begin{lstlisting}
- mul x y = code mul x y;
- app f (a,b) = (f a, f b);
- fst (x,_) = x;
- double !x = (x, x);
- main = app fst (double (mul 5 10, mul 10 20));
-\end{lstlisting}
-
-In the call to \fuspel{double}, both \fuspel{mul 5 10} and \fuspel{mul 10 20}
-are fully rewritten due to the strictness annotation. However, only the first
-elements of the resulting tuples are used: the result is \fuspel{(50,50)}. We
-did not need to fully rewrite \fuspel{mul 10 20}, so the strictness annotation
-gave us more work.
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