Merge pull request #154 from andportnoy/master

Minor typo and formatting fixes

book.tex

@@ -560,7 +560,7 @@ called \emph{parsing}\index{subject}{parsing}\python{\ and is studied in
   chapter~\ref{ch:parsing}}.
 \racket{This book does not cover the theory and implementation of parsing.
   We refer the readers interested in parsing to the thorough treatment
-  of parsing by \citet{Aho:2006wb}.}%
+  of parsing by \citet{Aho:2006wb}. }%
 %
 \racket{A parser is provided in the support code for translating from
   concrete to abstract syntax.}%
@@ -995,7 +995,7 @@ combine several right-hand sides into a single rule.
 
 The concrete syntax for \LangInt{} is shown in
 figure~\ref{fig:r0-concrete-syntax} and the abstract syntax for
-\LangInt{} is shown in figure~\ref{fig:r0-syntax}.%
+\LangInt{} is shown in figure~\ref{fig:r0-syntax}. %
 %
 \racket{The \code{read-program} function provided in
   \code{utilities.rkt} of the support code reads a program from a file
@@ -1450,7 +1450,7 @@ figure~\ref{fig:interp_Lint}.
     [(Prim 'read '())
      (define r (read))
      (cond [(fixnum? r) r]
-           [else (error 'interp_exp "read expected an integer" r)])]
+           [else (error 'interp_exp "read expected an integer: ~v" r)])]
     [(Prim '- (list e))
      (define v (interp_exp e))
      (fx- 0 v)]
@@ -2975,7 +2975,7 @@ become local variables whose scope is the entire program, which would
 confuse variables with the same name.}
 %
 \racket{We place \key{remove\_complex\_operands} before \key{explicate\_control}
-because the later removes the \key{let} form, but it is convenient to
+because the latter removes the \key{let} form, but it is convenient to
 use \key{let} in the output of \key{remove\_complex\_operands}.}
 %
 \racket{The ordering of \key{uniquify} with respect to