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<A NAME=DEFINE>

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



<B>DEFINE</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>command</B><P>
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The command <em>define</em> allows you to supply a new name for an identifier 
or replace it by any valid REDUCE expression. 
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syntax: </H3>
<em>define</em>&lt;identifier&gt;<em>=</em>&lt;substitution&gt; 
 {<em>,</em>&lt;identifier&gt;<em>=</em>&lt;substitution&gt;}* 
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&lt;identifier&gt; is any valid REDUCE identifier, &lt;substitution&gt; can be a
 
number, an identifier, an operator, a reserved word, or an expression. 
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examples: </H3>
<P><PRE><TT>

define is= :=, xx=y+z; 


a is 10; 

  A := 10 



xx**2; 

   2             2
  Y   + 2*Y*Z + Z  



xx := 10; 

  Y + Z := 10

</TT></PRE><P>The renaming is done at the input level, and therefore takes prece
dence 
over any other replacement or substitution declared for the same identifier. 
It remains in effect until the end of the REDUCE session. Be careful with 
it, since you cannot easily undo it without ending the session. 
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