Fixes to address Julie's comments

Author: krame505

doc/libraries_ref_guide/LibDoc/Prelude.tex

@@ -4372,7 +4372,7 @@ \subsubsection{String type pseudo-functions}
 \te{stringOf}&Converts a string type into its String value.\\
 \cline{2-2}
 &\begin{libverbatim}
-function String valueOf (t) ;
+function String stringOf (t) ;
 \end{libverbatim}
 \\
 \hline
@@ -4387,7 +4387,7 @@ \subsubsection{String type pseudo-functions}
 \hline
 \te{TStrCat}&\verb'TStrCat#(s1,s2)'&Concatenate $s1$ and $s2$\\
 \hline
-\te{TNumToStr}&\verb'TNumToStr#(n1)'&Convert numeric type $n$ to a string type\\
+\te{TNumToStr}&\verb'TNumToStr#(n)'&Convert numeric type $n$ to a string type\\
 \hline
 \end{tabular}
 \end{center}

src/comp/Pred.hs

@@ -261,7 +261,7 @@ expandSyn t0 = exp [] t0 []
         truncType k n t = internalError ("expandSyn,truncType\n" ++ ppReadable (k, n, t0, t))
 
 isTFun :: Id -> Bool
-isTFun i = i `elem` numOpNames
+isTFun i = i `elem` numOpNames ++ strOpNames
 
 apTFun :: Type -> Id -> [Type] -> Type
 apTFun _ i [TCon (TyNum x px), TCon (TyNum y py)] | Just n <- opNumT i [x, y] = TCon (TyNum n p')