some rules on syntax

docs/roqfy.tex

@@ -19,6 +19,21 @@
 \begin{document}
 \maketitle
 
+\section{Syntax}
+
+\subsection{Lexing}
+
+Comments start with \verb,(*, and end with \verb,*),. They can be nested.
+Strings start with \verb,", and end with \verb,",. They can contain evaluatable expressions in \verb,{, \verb,}, brackets.
+Thus strings get split into multiple tokens (\texttt{<string\_start> <string>$^?$ <tokens...> <string>$^?$ <string\_end>}).
+For these two features, the lexer contains stack handling. Whitespace separated tokens.
+
+\begin{tabular}{cc}
+Token & rule \\
+Integer & \texttt{[1-9][0-9]$^+$|0x[0-9a-fA-F]$^+$} \\
+Identifier & Unicode-XID (\texttt{<XID\_start><XID\_continue>$^*$}) \\
+\end{tabular}
+
 \section{Types}
 
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