Update docs

doc/BSV_ref_guide/BSV_lang.tex

@@ -3972,14 +3972,15 @@ \subsection{Type synonyms}
 
 \index{Alias}
 \index{NumAlias}
+\index{StrAlias}
 
 The \te{typedef} statement must always be at the top level of a
 package, not within a module.  To introduce a local name within a
-module, use \te{Alias} or \te{NumAlias} (see \LibRefGuide).  Since
+module, use \te{Alias}, \te{NumAlias} or \te{StrAlias} (see \LibRefGuide).  Since
 these introduce new names which are type variables as opposed to
 types, the new names must begin with lower case letters.
-\te{NumAlias} is used to give new names to numeric types, while
-\te{Alias} is used for types which can be the types of variables.
+\te{Alias} is used for types which can be the types of variables,
+while \te{NumAlias} and \te{StrAlias} are used to give new names to numeric and string types.
 Example:
 
 \begin{verbatim}

doc/libraries_ref_guide/LibDoc/Prelude.tex

@@ -48,6 +48,8 @@ \subsection{Type classes}
 \hline
 \te{NumAlias} & Types which give a new name to a numeric type.\\
 \hline
+\te{StrAlias} & Types which give a new name to a string type.\\
+\hline
 \te{FShow} & Types which can convert a value to a \te{Fmt}
 representation for use with \te{\$display} system tasks.\\
 \hline
@@ -1457,8 +1459,10 @@ \subsubsection{Alias and NumAlias}
 \label{sec-alias}
 \index{Alias}
 \index{NumAlias}
-\index[typeclass]{NumAlias}
+\index{StrAlias}
 \index[typeclass]{Alias}
+\index[typeclass]{NumAlias}
+\index[typeclass]{StrAlias}
 
 \te{Alias} specifies that two types can be used interchangeably,
 providing a way to introduce local names for types within a module.
@@ -1480,6 +1484,15 @@ \subsubsection{Alias and NumAlias}
 endtypeclass
 \end{verbatim}
 
+\te{StrAlias} is used to give a new name to a string type.
+
+\begin{verbatim}
+typeclass StrAlias#(string type a, string type b)
+   dependencies (a determines b,
+                 b determines a);
+endtypeclass
+\end{verbatim}
+
 {\bf Examples}
 \begin{verbatim}
    Alias#(fp, FixedPoint#(i,f));
@@ -4154,7 +4167,7 @@ \subsubsection{Rules}
 
 
 %================================================================
-\subsection{Operations on Numeric Types}
+\subsection{Operations on Numeric and String Types}
 
 \subsubsection{Size Relationship/Provisos}
 
@@ -4338,6 +4351,46 @@ \subsubsection{valueOf and SizeOf pseudo-functions}
    Bit#(SizeOf#(any_type)) = pack(structIn);
 \end{libverbatim}
 
+% ================================================================
+\subsubsection{String type pseudo-functions}
+\index{stringOf@\texttt{valueOf} (pseudo-function of types)}
+\index{TStrCat@\texttt{TStrCat} (pseudo-function on types)}
+\index{TNumToStr@\texttt{TNumToStr} (pseudo-function on types)}
+\index[function]{Prelude!stringOf}
+\index[function]{Prelude!TStrCat}
+\index[function]{Prelude!TNumToStr}
+
+Prelude also provides similar pseudo-functions for string types.
+The pseudo-function \te{stringOf} is used to convert a string type into a \te{String} value.
+The type-level pseudo-function \te{TStrCat} is used to concatenate two string types,
+and \te{TNumToStr} is used to convert a numeric type into a string type.
+
+\begin{center}
+\begin{tabular}{|p{1 in}|p{4.6 in}|}
+\hline
+& \\
+\te{stringOf}&Converts a string type into its String value.\\
+\cline{2-2}
+&\begin{libverbatim}
+function String valueOf (t) ;
+\end{libverbatim}
+\\
+\hline
+\end{tabular}
+\end{center}
+
+\begin{center}
+\begin{tabular}{|p {1 in}|p{1.5 in}| p{2.0 in}|}
+\hline
+Type Function& Type Relationship& Description\\
+\hline
+\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\\
+\hline
+\end{tabular}
+\end{center}
 
 % ================================================================
 \subsection{Registers and Wires}