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<A NAME=EVENP>

<TITLE>EVENP</TITLE></A>
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<B>EVENP</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>evenp</em> logical operator returns 
<A HREF=r37_0122.html>true</A> if its argument is an 
even integer, and 
<A HREF=r37_0014.html>nil</A> if its argument is an odd integer. An error 
message is returned if its argument is not an integer. 
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syntax: </H3>
<em>evenp</em>(&lt;integer&gt;) or <em>evenp</em> &lt;integer&gt; 
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&lt;integer&gt; must evaluate to an integer. 
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examples: </H3>
<P><PRE><TT>
aa := 1782; 

  AA := 1782 


if evenp aa then yes else no; 

  YES 


if evenp(-3) then yes else no; 

  NO 

</TT></PRE><P>Although you would not ordinarily enter an expression such as the 
last 
example above, note that the negative term must be enclosed in parentheses 
to be correctly parsed. The <em>evenp</em> operator can only be used in 
conditional statements such as <em>if</em>...<em>then</em>...<em>else</em> 
or <em>while</em>...<em>do</em>. 
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