File r37/lisp/csl/html/r37_0038.html artifact 0d64da7afd part of check-in 955d0a90a7

<A NAME=group>

<TITLE>group</TITLE></A>
<b><a href=r37_idx.html>INDEX</a></b><p><p>



<B><<</B> _ _ _ <B>GROUP</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>command</B><P>
<P>
 
The <em>&lt;&lt;</em>...<em>&gt;&gt;</em> command is a group statement, 
used to group statements 
together where REDUCE expects a single statement. 
<P>
<P>
 <P> <H3> 
syntax: </H3>
<em>&lt;&lt;</em>&lt;statement&gt;{; &lt;statement&gt; <em>or</em> 
 &lt;statement&gt;}* <em>&gt;&gt;</em> 
<P>
<P>
<P>
&lt;statement&gt; may be any valid REDUCE statement or expression. 
<P>
<P>
 <P> <H3> 
examples: </H3>
<P><PRE><TT>
a := 2; 

  A := 2 


if a &lt; 5 then &lt;&lt;b := a + 10; write b&gt;&gt;; 


  12 


&lt;&lt;d := c/15; f := d + 3; f**2&gt;&gt;;
 

   2
  C  + 90*C + 202
  ----------------
        225

</TT></PRE><P>The value returned from a group statement is the value of the last
 
individual statement executed inside it. Note that when a semicolon is 
placed between the last statement and the closing brackets, 0 or 
 nil is returned. Group statements are often used in the 
consequence portions of 
<A HREF=r37_0052.html>if</A>...<em>then</em>, 

<A HREF=r37_0056.html>repeat</A>...<em>until</em>, and 

<A HREF=r37_0228.html>while</A>...<em>do</em> 
clauses. They may also be used in interactive 
operation to execute several statements at one time. Statements inside 
the group statement are separated by semicolons or dollar signs. 
<P>
<P>
<P>
<P>