updating the introduction

[helm.git] / helm / mathql / doc / mathql_introduction_textual.tex

diff --git a/helm/mathql/doc/mathql_introduction_textual.tex b/helm/mathql/doc/mathql_introduction_textual.tex
index dd225479ce475f7168b3a07ff6d19912f46c8a52..2899a24ce4054e5bbef19c1013e3b567690d8082 100644 (file)
--- a/helm/mathql/doc/mathql_introduction_textual.tex
+++ b/helm/mathql/doc/mathql_introduction_textual.tex
@@ -86,8 +86,8 @@ The meaning of the escaped sequences is shown in \figref{EscTS}
 
 {\MathQL} character escaping syntax aims at complying with W3C character model
 for the World Wide Web \cite{W3Ca} which recommends a support for standard
-Unicode characters (U+0000 to U+FFFF) and escape sequences with
-start/end delimiters.
+Unicode characters (U+0000 to U+FFFF) and escape sequences with start/end
+delimiters.
 In particular {\MathQL} escape delimiters (backslash and caret) are chosen
 among the {\em unwise} characters for URI references (see \cite{URI}) because
 URI references are the natural content of constant strings and these
@@ -95,7 +95,8 @@ characters should not be so frequent in them.
 
 Query expressions can contain variables for {\av}'s (production \GP{avar})
 and variables for {\av} sets, {\ie} for query results (production \GP{svar})
-according to the syntax of \figref{VarTS}.
+according to the syntax of \figref{VarTS}.%
+\footnote{This syntax resembles the one of programming languages identifiers.}
 
 \begin{figure}[ht]
 \begin{footnotesize} \begin{verbatim}
@@ -160,14 +161,19 @@ The syntax of result expressions (production \GP{avs}) is described in
 \caption{Textual syntax of results} \label{ResultTS}
 \end{figure}
 
-\xcomment {
+The textual syntax of the language extension provided by the basic library
+is in \figref{BasicTS}.
 
 \begin{figure}[ht]
 \begin{footnotesize} \begin{verbatim}
-            |   "select" <avar> "from" <query> "where" <query>
+<query> ::= "empty" | "false" | "true"
+        |   "not" <query>
+        |   <query> [ "and" | "or" | "xor"| "sub" | "meet" | "eq" | "le"| "lt" ] <query>
+        |   <query> [ "union" | "intersect" ] <query> | { <queries> }  
+        |   "if" <query> "then" <query> "else" <query>
+        |   "select" <avar> "from" <query> "where" <query>
 \end{verbatim} \end{footnotesize}
 \vskip-1pc
-\caption{Textual syntax of basic query extensions} \label{BasicTS}
+\caption{Textual syntax of basic extension} \label{BasicTS}
 \end{figure}
 
-}