added !!!;
added is_semicolon;
export incr_line, keep_line, scan_blank, scan_string;
added source_proper;
added make_lexicon;
tuned;
%FIXME
%\chapter{Basic Concepts}\label{ch:basics}
%\section{The Isar proof language}
%%% Local Variables:
%%% mode: latex
%%% TeX-master: "isar-ref"
%%% End: