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book.tex

@@ -3452,6 +3452,8 @@ error.  If it does, there is something wrong with your type checker.
 \section{The $C_1$ Language}
 \label{sec:c1}
 
+UNDER CONSTRUCTION
+
 The $R_2$ language adds Booleans and conditional expressions to $R_1$.
 As with $R_1$, we shall compile to a C-like intermediate language, but
 we need to grow that intermediate language to handle the new features