Hadn't realized the codeexample environment only allowed a single `…

…\tikz` command. Now using a `tikzpicture`.

doc/generic/pgf/text-en/pgfmanual-en-tutorial.tex

@@ -1104,10 +1104,12 @@ \subsection{Repeating Things: For-Loops}
 rounding errors:
 %
 \begin{codeexample}[]
-\tikz \foreach \x in {-1,-0.5,...,1}
-       \draw (\x cm,-1pt) -- (\x cm,1pt);
-\tikz \foreach \x in {-1,-0.8,...,1}
-       \draw (\x cm,-7pt) -- (\x cm,-5pt);
+\begin{tikzpicture}
+  \foreach \x in {-1,-0.5,...,1}
+    \draw (\x cm,-1pt) -- (\x cm,1pt);
+  \foreach \x in {-1,-0.8,...,1}
+    \draw (\x cm,-7pt) -- (\x cm,-5pt);
+\end{tikzpicture}
 \end{codeexample}
 
 We can also nest loops to create interesting effects: