File r37/lisp/csl/html/r37_0116.html artifact 2fd1ba89ea part of check-in 3c4d7b69af

<A NAME=MEMBER>

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



<B>MEMBER</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
<P>
 
 <P>
<P>
 <P> <H3> 
syntax: </H3>
&lt;expression&gt; <em>member</em> &lt;list&gt; 
<P>
<P>
<P>
<em>member</em>is an infix binary comparison operator that evaluates to 

<A HREF=r37_0122.html>true</A> if &lt;expression&gt; is 
<A HREF=r37_0110.html>equal</A> to a member of 
the 
<A HREF=r37_0053.html>list</A> &lt;list&gt;. 
<P>
<P>
 <P> <H3> 
examples: </H3>
<P><PRE><TT>
if a member {a,b} then 1 else 0; 

  1 


if 1 member(1,2,3) then a else b; 

  a 


if 1 member(1.0,2) then a else b; 

  b

</TT></PRE><P>Logical operators can only be used in conditional statements such 
as 
<P>
<P>
<em>if</em>...<em>then</em>...<em>else</em> or <em>while</em>...<em>do</em>. 
&lt;member&gt; can also be used as a prefix operator. However, this use 
is not encouraged. Finally, 
<A HREF=r37_0110.html>equal</A> (<em>=</em>) is used for the test 
within the list, so expressions must be of the same type to match. 
<P>
<P>
<P>