New syntax for match patterns in terms and in patterns.

[helm.git] / matita / help / C / sec_terms.xml

diff --git a/matita/help/C/sec_terms.xml b/matita/help/C/sec_terms.xml
index add3ba750bf181683c65ae473be1269cc745377c..3cae2f84c1866ad13d858e14eb32953176c38c13 100644 (file)
--- a/matita/help/C/sec_terms.xml
+++ b/matita/help/C/sec_terms.xml
@@ -198,7 +198,7 @@
        <entry id="grammar.rec_def">&rec_def;</entry>
        <entry>::=</entry>
        <entry>
-         &id; [&id;|<emphasis role="bold">(</emphasis>&id;[<emphasis role="bold">,</emphasis>&term;]… <emphasis role="bold">:</emphasis>&term;<emphasis role="bold">)</emphasis>]…
+         &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>
@@ -285,7 +285,7 @@
       <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>
@@ -387,6 +387,18 @@
       <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>
@@ -417,6 +429,11 @@
      <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;]…]…
@@ -557,7 +574,7 @@
        <row>
         <entry/>
         <entry>|</entry>
-        <entry><emphasis role="bold">in match</emphasis> &term;
+        <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>
@@ -573,7 +590,7 @@
        <row>
        <entry id="grammar.path">&path;</entry>
        <entry>::=</entry>
-        <entry><emphasis>〈〈any &sterm; whithout 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>
+        <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>
@@ -586,6 +603,26 @@
        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
@@ -687,6 +724,36 @@
      </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>