fix ignore WS

Author: jsiek

book.tex

@@ -26,7 +26,7 @@
 
 \def\racketEd{0}
 \def\pythonEd{1}
-\def\edition{0}
+\def\edition{1}
 
 % material that is specific to the Racket edition of the book
 \newcommand{\racket}[1]{{\if\edition\racketEd{#1}\fi}}
@@ -4649,8 +4649,8 @@ \section{From Parse Trees to Abstract Syntax Trees}
   white space, so we recommend using Lark's \code{\%ignore} directive
   as follows.
 \begin{lstlisting}
-   WS: /[ \t\f\r\n]/+
-   %ignore WS
+  %import common.WS_INLINE
+  %ignore WS_INLINE
 \end{lstlisting}
 Change your compiler from chapter~\ref{ch:Lvar} to use your
 Lark parser instead of using the \code{parse} function from