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New syntax for match patterns in terms and in patterns.
[helm.git] / matita / help / C / sec_terms.xml
index fbf8dd4ef9cb614c7dfb52eb4c2fa80e1ab210b2..3cae2f84c1866ad13d858e14eb32953176c38c13 100644 (file)
        E.g.: [<emphasis role="bold">in</emphasis> &term;]</para></listitem>
     <listitem><para>Alternatives are put in square brakets and they are
        separated by vertical bars. E.g.: [<emphasis role="bold">&lt;</emphasis>|<emphasis role="bold">&gt;</emphasis>]</para></listitem>
-    <listitem><para>Repetition of sequences of elements are given by putting the
-    first sequence in square brackets, that are followed by three dots.
+    <listitem><para>Repetitions of a sequence of elements are given by putting the
+    sequence in square brackets, that are followed by three dots. The empty
+    sequence is a valid repetition.
     E.g.: [<emphasis role="bold">and</emphasis> &term;]…</para></listitem>
+    <listitem><para>Characters belonging to a set of characters are given
+     by listing the set elements in square brackets. Hyphens are used to
+     specify ranges of characters in the set.
+     E.g.: [<emphasis role="bold">a</emphasis>-<emphasis role="bold">zA</emphasis>-<emphasis role="bold">Z0</emphasis>-<emphasis role="bold">9_-</emphasis>]</para></listitem>
   </orderedlist>
   <sect1 id="terms_and_co">
   <title>Terms &amp; co.</title>
   <sect2 id="lexical">
   <title>Lexical conventions</title>
-  <para>
-    <table frame="all" rowsep="0" colsep="0">
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
+      <title>qstring</title>
+      <tgroup cols="4">
+      <tbody>
+       <row>
+       <entry id="grammar.qstring">&qstring;</entry>
+       <entry>::=</entry>
+        <entry><emphasis role="bold">&quot;</emphasis><emphasis>〈〈any sequence of characters excluded &quot;〉〉</emphasis><emphasis role="bold">&quot;</emphasis></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
       <title>id</title>
       <tgroup cols="4">
       <tbody>
        <row>
-       <entry id="id">&id;</entry>
+       <entry id="grammar.id">&id;</entry>
        <entry>::=</entry>
-       <entry><emphasis>〈〈&TODO;〉〉</emphasis></entry>
+        <entry><emphasis>〈〈any sequence of letters, underscores or valid <ulink type="http" url="http://www.w3.org/TR/2004/REC-xml-20040204/#NT-Digit">XML digits</ulink> prefixed by a latin letter ([a-zA-Z]) and post-fixed by a possible empty sequence of decorators ([?'`])〉〉</emphasis></entry>
        </row>
       </tbody>
      </tgroup>
     </table>
-    <table frame="all" rowsep="0" colsep="0">
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
       <title>nat</title>
       <tgroup cols="4">
       <tbody>
        <row>
-       <entry id="nat">&nat;</entry>
+       <entry id="grammar.nat">&nat;</entry>
        <entry>::=</entry>
-       <entry><emphasis>〈〈&TODO;〉〉</emphasis></entry>
+       <entry><emphasis>〈〈any sequence of valid <ulink type="http" url="http://www.w3.org/TR/2004/REC-xml-20040204/#NT-Digit">XML digits</ulink>〉〉</emphasis></entry>
        </row>
       </tbody>
      </tgroup>
     </table>
-    <table frame="all" rowsep="0" colsep="0">
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
+      <title>char</title>
+      <tgroup cols="4">
+      <tbody>
+       <row>
+       <entry id="grammar.char">&char;</entry>
+       <entry>::=</entry>
+       <entry>[<emphasis role="bold">a</emphasis>-<emphasis role="bold">zA</emphasis>-<emphasis role="bold">Z0</emphasis>-<emphasis role="bold">9_-</emphasis>]</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
+      <title>uri-step</title>
+      <tgroup cols="4">
+      <tbody>
+       <row>
+       <entry id="grammar.uri-step">&uri-step;</entry>
+       <entry>::=</entry>
+       <entry>&char;[&char;]…</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
       <title>uri</title>
       <tgroup cols="4">
       <tbody>
        <row>
-       <entry id="uri">&uri;</entry>
+       <entry id="grammar.uri">&uri;</entry>
        <entry>::=</entry>
-       <entry><emphasis>〈〈&TODO;〉〉</emphasis></entry>
+       <entry>[<emphasis role="bold">cic:/</emphasis>|<emphasis role="bold">theory:/</emphasis>]&uri-step;[<emphasis role="bold">/</emphasis>&uri-step;]…<emphasis role="bold">.</emphasis>&id;[<emphasis role="bold">.</emphasis>&id;]…[<emphasis role="bold">#xpointer(</emphasis>&nat;<emphasis role="bold">/</emphasis>&nat;[<emphasis role="bold">/</emphasis>&nat;]…<emphasis role="bold">)</emphasis>]</entry>
        </row>
       </tbody>
      </tgroup>
     </table>
-  </para>
   </sect2>
   <sect2 id="terms">
   <title>Terms</title>
+
+  <!-- ZACK: Sample EBNF snippet, see:
+  http://www.docbook.org/tdg/en/html/productionset.html -->
+  <!--
+  <productionset>
+    <title>Terms</title>
+    <production id="grammar.term">
+      <lhs>&term;</lhs>
+      <rhs>&sterm;</rhs>
+      <lineannotation></lineannotation>
+    </production>
+  </productionset>
+  -->
+
   <para>
-  <table frame="all" rowsep="0" colsep="0">
+  <table frame="topbot" rowsep="0" colsep="0" role="grammar">
     <title>Terms</title>
     <tgroup cols="4">
     <tbody>
      <row>
-      <entry id="term">&term;</entry>
+      <entry id="grammar.term">&term;</entry>
       <entry>::=</entry>
       <entry>&sterm;</entry>
       <entry>simple or delimited term</entry>
      <row>
       <entry/>
       <entry>|</entry>
-      <entry><emphasis role="bold">let</emphasis>
-      [<emphasis role="bold">co</emphasis>]<emphasis role="bold">rec</emphasis>
-      &id; [&id;|<emphasis role="bold">(</emphasis>&id;[<emphasis role="bold">,</emphasis>&term;]… <emphasis role="bold">:</emphasis>&term;<emphasis role="bold">)</emphasis>]… [<emphasis role="bold">on</emphasis> &nat;]
-      [<emphasis role="bold">:</emphasis> &term;]
-      <emphasis role="bold">≝</emphasis> &term;
+      <entry>
+       <emphasis role="bold">let</emphasis>
+       [<emphasis role="bold">co</emphasis>]<emphasis role="bold">rec</emphasis>
+       &rec_def;
       </entry>
       <entry>(co)recursive definitions</entry>
      </row>
       <entry/>
       <entry/>
       <entry>
-      [<emphasis role="bold">and</emphasis>
-      [&id;|<emphasis role="bold">(</emphasis>&id;[<emphasis role="bold">,</emphasis>&term;]… <emphasis role="bold">:</emphasis>&term;<emphasis role="bold">)</emphasis>]… [<emphasis role="bold">on</emphasis> &nat;]
-      [<emphasis role="bold">:</emphasis> &term;]
-      <emphasis role="bold">≝</emphasis> &term;]…
+      [<emphasis role="bold">and</emphasis> &rec_def;]…
       </entry>
       <entry/>
      </row>
       <entry>…</entry>
       <entry>user provided notation</entry>
      </row>
+      <row>
+       <entry id="grammar.rec_def">&rec_def;</entry>
+       <entry>::=</entry>
+       <entry>
+         &id; [&id;|<emphasis role="bold">_</emphasis>|<emphasis role="bold">(</emphasis>&id;[<emphasis role="bold">,</emphasis>&id;]… <emphasis role="bold">:</emphasis>&term;<emphasis role="bold">)</emphasis>]…
+       </entry>
+       <entry />
+      </row>
+      <row>
+       <entry />
+       <entry />
+       <entry>
+         [<emphasis role="bold">on</emphasis> &id;]
+         [<emphasis role="bold">:</emphasis> &term;]
+         <emphasis role="bold">≝</emphasis> &term;]
+       </entry>
+       <entry />
+      </row>
     </tbody>
    </tgroup>
   </table>
 
-  <table frame="all" rowsep="0" colsep="0">
+  <table frame="topbot" rowsep="0" colsep="0" role="grammar">
     <title>Simple terms</title>
     <tgroup cols="4">
     <tbody>
      <row>
-      <entry id="sterm">&sterm;</entry>
+      <entry id="grammar.sterm">&sterm;</entry>
       <entry>::=</entry>
       <entry><emphasis role="bold">(</emphasis>&term;<emphasis role="bold">)</emphasis></entry>
       <entry/>
       <entry><emphasis role="bold">Set</emphasis></entry>
       <entry>the impredicate sort of datatypes</entry>
      </row>
+     <row>
+      <entry/>
+      <entry>|</entry>
+      <entry><emphasis role="bold">CProp</emphasis></entry>
+      <entry>one fixed predicative sort of constructive propositions</entry>
+     </row>
      <row>
       <entry/>
       <entry>|</entry>
       <entry/>
       <entry>|</entry>
         <entry><emphasis role="bold">match</emphasis> &term; 
-        [ <emphasis role="bold">in</emphasis> &term; ]
+        [ <emphasis role="bold">in</emphasis> &id; ]
         [ <emphasis role="bold">return</emphasis> &term; ]
         <emphasis role="bold">with</emphasis>
       </entry>
       <entry/>
       <entry>
        <emphasis role="bold">[</emphasis> 
-       &match_pattern; <emphasis role="bold"> ⇒ </emphasis> &term;
-         [
-         <emphasis role="bold">|</emphasis>
-         &match_pattern; <emphasis role="bold"> ⇒ </emphasis> &term;
-         ]…<emphasis role="bold">]</emphasis> </entry>
+       &match_branch;[<emphasis role="bold">|</emphasis>&match_branch;]…
+       <emphasis role="bold">]</emphasis> 
+      </entry>
       <entry/>
      </row>
      <row>
    </tgroup>
   </table>
 
-  <table frame="all" rowsep="0" colsep="0">
+  <table frame="topbot" rowsep="0" colsep="0" role="grammar">
     <title>Arguments</title>
     <tgroup cols="4">
     <tbody>
      <row>
-      <entry id="args">&args;</entry>
+      <entry id="grammar.args">&args;</entry>
       <entry>::=</entry>
       <entry>
        <emphasis role="bold">_</emphasis>[<emphasis role="bold">:</emphasis> &term;]
       <entry><emphasis role="bold">(</emphasis>&id;[<emphasis role="bold">,</emphasis>&id;]…[<emphasis role="bold">:</emphasis> &term;]<emphasis role="bold">)</emphasis></entry>
       <entry/>
      </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <table frame="all" rowsep="0" colsep="0">
-    <title>Miscellaneous arguments</title>
-    <tgroup cols="4">
-    <tbody>
      <row>
-      <entry id="args2">&args2;</entry>
+      <entry id="grammar.args2">&args2;</entry>
       <entry>::=</entry>
       <entry>&id;</entry>
       <entry/>
    </tgroup>
   </table>
 
-  <table frame="all" rowsep="0" colsep="0">
+  <table frame="topbot" rowsep="0" colsep="0" role="grammar">
     <title>Pattern matching</title>
     <tgroup cols="4">
     <tbody>
+      <row>
+       <entry id="grammar.match_branch">&match_branch;</entry>
+       <entry>::=</entry>
+       <entry>&match_pattern; <emphasis role="bold">⇒</emphasis> &term;</entry>
+       <entry />
+      </row>
      <row>
-      <entry id="match_pattern">&match_pattern;</entry>
+      <entry id="grammar.match_pattern">&match_pattern;</entry>
       <entry>::=</entry>
       <entry>&id;</entry>
       <entry>0-ary constructor</entry>
       <entry><emphasis role="bold">(</emphasis>&id; &id; [&id;]…<emphasis role="bold">)</emphasis></entry>
       <entry>n-ary constructor (binds the n arguments)</entry>
      </row>
+     <row>
+      <entry/>
+      <entry>|</entry>
+      <entry>&id; &id; [&id;]…</entry>
+      <entry>n-ary constructor (binds the n arguments)</entry>
+     </row>
+     <row>
+      <entry/>
+      <entry>|</entry>
+      <entry><emphasis role="bold">_</emphasis></entry>
+      <entry>any remaining constructor (ignoring its arguments)</entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
      <command>f</command> must be defined by means of tactics.</para>
     <para>Notice that the command is equivalent to <command>theorem f: T ≝ t</command>.</para>
   </sect2>
+  <sect2 id="letrec">
+    <title><emphasis role="bold">letrec</emphasis> &TODO;</title>
+    <titleabbrev>&TODO;</titleabbrev>
+    <para>&TODO;</para>
+  </sect2>
   <sect2 id="inductive">
     <title>[<emphasis role="bold">inductive</emphasis>|<emphasis role="bold">coinductive</emphasis>] &id; [&args2;]… <emphasis role="bold">:</emphasis> &term; <emphasis role="bold">≝</emphasis> [<emphasis role="bold">|</emphasis>] [&id;<emphasis role="bold">:</emphasis>&term;] [<emphasis role="bold">|</emphasis> &id;<emphasis role="bold">:</emphasis>&term;]…
 [<emphasis role="bold">with</emphasis> &id; <emphasis role="bold">:</emphasis> &term; <emphasis role="bold">≝</emphasis> [<emphasis role="bold">|</emphasis>] [&id;<emphasis role="bold">:</emphasis>&term;] [<emphasis role="bold">|</emphasis> &id;<emphasis role="bold">:</emphasis>&term;]…]…
     <para>Notice that the command is equivalent to <command>definition f: T ≝ t</command>.</para>
    </sect2>
    <sect2 id="variant">
-    <title><emphasis role="bold">variant</emphasis> &id;[<emphasis role="bold">:</emphasis> &term;] [<emphasis role="bold">≝</emphasis> &term;]</title>
+    <title><emphasis role="bold">variant</emphasis> &id;<emphasis role="bold">:</emphasis> &term; <emphasis role="bold">≝</emphasis> &term;</title>
     <titleabbrev>variant</titleabbrev>
     <para><userinput>variant f: T ≝ t</userinput></para>
     <para>Same as <command>theorem f: T ≝ t</command>, but it does not
    </sect2>
   </sect1>
 
+  <sect1 id="tacticargs">
+   <title>Tactic arguments</title>
+   <para>This section documents the syntax of some recurring arguments for
+    tactics.</para>
+
+    <sect2 id="introsspec">
+    <title>intros-spec</title>
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
+      <title>intros-spec</title>
+      <tgroup cols="4">
+      <tbody>
+       <row>
+       <entry id="grammar.intros-spec">&intros-spec;</entry>
+       <entry>::=</entry>
+        <entry>[&nat;] [<emphasis role="bold">(</emphasis>[&id;]…<emphasis role="bold">)</emphasis>]</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+        <para>The natural number is the number of new hypotheses to be introduced. The list of identifiers gives the name for the first hypotheses.</para>
+    </sect2>
+
+    <sect2 id="pattern">
+    <title>pattern</title>
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
+      <title>pattern</title>
+      <tgroup cols="4">
+      <tbody>
+       <row>
+       <entry id="grammar.pattern">&pattern;</entry>
+       <entry>::=</entry>
+        <entry><emphasis role="bold">in</emphasis>
+          [&id;[<emphasis role="bold">:</emphasis> &path;]]…
+          [<emphasis role="bold">⊢</emphasis> &path;]]</entry>
+        <entry>simple pattern</entry>
+       </row>
+       <row>
+        <entry/>
+        <entry>|</entry>
+        <entry><emphasis role="bold">in match</emphasis> &path;
+          [<emphasis role="bold">in</emphasis>
+          [&id;[<emphasis role="bold">:</emphasis> &path;]]…
+          [<emphasis role="bold">⊢</emphasis> &path;]]</entry>
+        <entry>full pattern</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
+      <title>path</title>
+      <tgroup cols="4">
+      <tbody>
+       <row>
+       <entry id="grammar.path">&path;</entry>
+       <entry>::=</entry>
+        <entry><emphasis>〈〈any &sterm; without occurrences of <emphasis role="bold">Set</emphasis>, <emphasis role="bold">Prop</emphasis>, <emphasis role="bold">CProp</emphasis>, <emphasis role="bold">Type</emphasis>, &id;, &uri; and user provided notation; however, <emphasis role="bold">%</emphasis> is now an additional production for &sterm;〉〉</emphasis></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+    <para>A <emphasis>path</emphasis> locates zero or more subterms of a given term by mimicking the term structure up to:</para>
+    <orderedlist>
+      <listitem><para>Occurrences of the subterms to locate that are
+       represented by <emphasis role="bold">%</emphasis>.</para></listitem>
+      <listitem><para>Subterms without any occurrence of subterms to locate
+       that can be represented by <emphasis role="bold">?</emphasis>.
+       </para></listitem>
+    </orderedlist>
+    <para>Warning: the format for a path for a <emphasis role="bold">match</emphasis> … <emphasis role="bold">with</emphasis>
+     expression is restricted to: <emphasis role="bold">match</emphasis> &path;
+     <emphasis role="bold">with</emphasis>
+     <emphasis role="bold">[</emphasis>
+     <emphasis role="bold">_</emphasis>
+     <emphasis role="bold">⇒</emphasis>
+     &path;
+     <emphasis role="bold">|</emphasis> …
+     <emphasis role="bold">|</emphasis>
+     <emphasis role="bold">_</emphasis>
+     <emphasis role="bold">⇒</emphasis>
+     &path;
+     <emphasis role="bold">]</emphasis>
+     Its semantics is the following: the n-th 
+     &quot;<emphasis role="bold">_</emphasis>
+     <emphasis role="bold">⇒</emphasis>
+     &path;&quot; branch is matched against the n-th constructor of the
+     inductive data type. The head λ-abstractions of &path; are matched
+     against the corresponding constructor arguments. 
+    </para>
+    <para>For instance, the path
+      <userinput>∀_,_:?.(? ? % ?)→(? ? ? %)</userinput>
+       locates at once the subterms
+      <userinput>x+y</userinput> and <userinput>x*y</userinput> in the
+      term <userinput>∀x,y:nat.x+y=1→0=x*y</userinput>
+      (where the notation <userinput>A=B</userinput> hides the term
+      <userinput>(eq T A B)</userinput> for some type <userinput>T</userinput>).
+    </para>
+    <para>A <emphasis>simple pattern</emphasis> extends paths to locate
+     subterms in a whole sequent. In particular, the pattern
+     <userinput>in H: p  K: q ⊢ r</userinput> locates at once all the subterms
+     located by the pattern <userinput>r</userinput> in the conclusion of the
+     sequent and by the patterns <userinput>p</userinput> and
+     <userinput>q</userinput> in the hypotheses <userinput>H</userinput>
+     and <userinput>K</userinput> of the sequent.
+    </para>
+    <para>If no list of hypotheses is provided in a simple pattern, no subterm
+     is selected in the hypothesis. If the <userinput>⊢ p</userinput>
+     part of the pattern is not provided, no subterm will be matched in the
+     conclusion if at least one hypothesis is provided; otherwise the whole
+     conclusion is selected.
+    </para>
+    <para>Finally, a <emphasis>full pattern</emphasis> is interpreted in three
+     steps. In the first step the <userinput>match T in</userinput>
+     part is ignored and a set <emphasis>S</emphasis> of subterms is
+     located as for the case of
+     simple patterns. In the second step the term <userinput>T</userinput>
+     is parsed and interpreted in the context of each subterm
+     <emphasis>s ∈ S</emphasis>. In the last term for each
+     <emphasis>s ∈ S</emphasis> the interpreted term <userinput>T</userinput>
+     computed in the previous step is looked for. The final set of subterms
+     located by the full pattern is the set of occurrences of
+     the interpreted <userinput>T</userinput> in the subterms <emphasis>s</emphasis>.
+    </para>
+    <para>A full pattern can always be replaced by a simple pattern,
+      often at the cost of increased verbosity or decreased readability.</para>
+    <para>Example: the pattern
+      <userinput>⊢ in match x+y in ∀_,_:?.(? ? % ?)</userinput>
+      locates only the first occurrence of <userinput>x+y</userinput>
+      in the sequent <userinput>x,y: nat ⊢ ∀z,w:nat. (x+y) * (z+w) =
+      z * (x+y) + w * (x+y)</userinput>. The corresponding simple pattern
+      is <userinput>⊢ ∀_,_:?.(? ? (? % ?) ?)</userinput>.
+    </para>
+    <para>Every tactic that acts on subterms of the selected sequents have
+     a pattern argument for uniformity. To automatically generate a simple
+     pattern:</para>
+    <orderedlist>
+     <listitem><para>Select in the current goal the subterms to pass to the
+      tactic by using the mouse. In order to perform a multiple selection of
+      subterms, hold the Ctrl key while selecting every subterm after the
+      first one.</para></listitem>
+     <listitem><para>From the contextual menu select &quot;Copy&quot;.</para></listitem>
+     <listitem><para>From the &quot;Edit&quot; or the contextual menu select
+      &quot;Paste as pattern&quot;</para></listitem>
+    </orderedlist>
+    </sect2>
+
+    <sect2 id="reduction-kind">
+    <title>reduction-kind</title>
+    <para>Reduction kinds are normalization functions that transform a term
+     to a convertible but simpler one. Each reduction kind can be used both
+     as a tactic argument and as a stand-alone tactic.</para>
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
+      <title>reduction-kind</title>
+      <tgroup cols="4">
+      <tbody>
+       <row>
+       <entry id="grammar.reduction-kind">&reduction-kind;</entry>
+       <entry>::=</entry>
+        <entry><emphasis role="bold">normalize</emphasis></entry>
+        <entry>Computes the βδιζ-normal form</entry>
+       </row>
+       <row>
+        <entry/>
+        <entry>|</entry>
+        <entry><emphasis role="bold">reduce</emphasis></entry>
+        <entry>Computes the βδιζ-normal form</entry>
+       </row>
+       <row>
+        <entry/>
+        <entry>|</entry>
+        <entry><emphasis role="bold">simplify</emphasis></entry>
+        <entry>Computes a form supposed to be simpler</entry>
+       </row>
+       <row>
+        <entry/>
+        <entry>|</entry>
+        <entry><emphasis role="bold">unfold</emphasis> [&sterm;]</entry>
+        <entry>δ-reduces the constant or variable if specified, or that
+         in head position</entry>
+       </row>
+       <row>
+        <entry/>
+        <entry>|</entry>
+        <entry><emphasis role="bold">whd</emphasis></entry>
+        <entry>Computes the βδιζ-weak-head normal form</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+    </sect2>
+
+    <sect2 id="auto-params">
+    <title>auto-params</title>
+    <para>&TODO;</para>
+    <table frame="topbot" rowsep="0" colsep="0" role="grammar">
+      <title>reduction-kind</title>
+      <tgroup cols="4">
+      <tbody>
+       <row>
+       <entry id="grammar.autoparams">&autoparams;</entry>
+       <entry>::=</entry>
+        <entry><emphasis role="bold">depth=&nat;</emphasis></entry>
+        <entry>&TODO;</entry>
+       </row>
+       <row>
+        <entry/>
+        <entry>|</entry>
+        <entry><emphasis role="bold">width=&nat;</emphasis></entry>
+        <entry>&TODO;</entry>
+       </row>
+       <row>
+        <entry/>
+        <entry>|</entry>
+        <entry><emphasis role="bold">&TODO;</emphasis></entry>
+        <entry>&TODO;</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+    </sect2>
+  </sect1>
+
 </chapter>