Add psql \ev and \sv commands for editing and showing view definitions.

These are basically just like the \ef and \sf commands for functions.

Petr Korobeinikov, reviewed by Jeevan Chalke, some changes by me

Author: tglsfdc

doc/src/sgml/ref/psql-ref.sgml

@@ -1650,6 +1650,32 @@ Tue Oct 26 21:40:57 CEST 1999
       </varlistentry>
 
 
+      <varlistentry>
+        <term><literal>\ev <optional> <replaceable class="parameter">view_name</> <optional>  <replaceable class="parameter">line_number</> </optional> </optional> </literal></term>
+
+        <listitem>
+        <para>
+         This command fetches and edits the definition of the named view,
+         in the form of a <command>CREATE OR REPLACE VIEW</> command.
+         Editing is done in the same way as for <literal>\edit</>.
+         After the editor exits, the updated command waits in the query buffer;
+         type semicolon or <literal>\g</> to send it, or <literal>\r</>
+         to cancel.
+        </para>
+
+        <para>
+         If no view is specified, a blank <command>CREATE VIEW</>
+         template is presented for editing.
+        </para>
+
+        <para>
+         If a line number is specified, <application>psql</application> will
+         position the cursor on the specified line of the view definition.
+        </para>
+        </listitem>
+      </varlistentry>
+
+
       <varlistentry>
         <term><literal>\encoding [ <replaceable class="parameter">encoding</replaceable> ]</literal></term>
 
@@ -2521,6 +2547,25 @@ testdb=&gt; <userinput>\setenv LESS -imx4F</userinput>
       </varlistentry>
 
 
+      <varlistentry>
+        <term><literal>\sv[+] <replaceable class="parameter">view_name</> </literal></term>
+
+        <listitem>
+         <para>
+          This command fetches and shows the definition of the named view,
+          in the form of a <command>CREATE OR REPLACE VIEW</> command.
+          The definition is printed to the current query output channel,
+          as set by <command>\o</command>.
+         </para>
+
+         <para>
+          If <literal>+</literal> is appended to the command name, then the
+          output lines are numbered from 1.
+         </para>
+        </listitem>
+      </varlistentry>
+
+
       <varlistentry>
         <term><literal>\t</literal></term>
         <listitem>
@@ -3554,9 +3599,10 @@ $endif
 
     <listitem>
      <para>
-      Editor used by the <command>\e</command> and
-      <command>\ef</command> commands.  The variables are examined in
-      the order listed; the first that is set is used.
+      Editor used by the <command>\e</command>, <command>\ef</command>,
+      and <command>\ev</command> commands.
+      These variables are examined in the order listed;
+      the first that is set is used.
      </para>
 
      <para>
@@ -3571,7 +3617,8 @@ $endif
 
     <listitem>
      <para>
-      When <command>\e</command> or <command>\ef</command> is used
+      When <command>\e</command>, <command>\ef</command>, or
+      <command>\ev</command> is used
       with a line number argument, this variable specifies the
       command-line argument used to pass the starting line number to
       the user's editor.  For editors such as <productname>Emacs</> or