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<h3 class="section">2.8 Conditionals</h3>
<p>Any value can be related to another value. 78 is less than 85. 2 equals
2. "Hi" is not "Bye". Enigma comes with a basic set of functions that
can be used to test these relations. The functions <code>greater</code>,
<code>lesser</code>, <code>equal</code>, <code>not</code>, <code>or</code> and <code>and</code> are
available. These functions return either true or false. To run a
function on the condition that a relational function has returned true,
use the function <code>act</code>.
<p>While <code>lesser</code> and <code>greater</code> are aimed at numbers only,
and <code>and</code>, <code>or</code> and <code>not</code> are aimed at booleans only,
<code>equal</code> can be used on all objects. It tests for all equalities.
<pre class="verbatim">2 = a;
4 = b;
a 2 ! add | temp b ! equal = cond1;
"47" ! num | temp 48 ! greater = cond2;
cond1 cond2 ! and | temp write stdout "4 = 4 and 47 > 48\n" ! act;
cond1 cond2 ! or | temp write stdout "4 = 4 or 47 > 48\n" ! act;
cond2 ! not | cond1 temp ! and | temp write stdout "4 = 4 and !(47 >
48)\n" ! act;
</pre>
<p>Even simpler, one can do this (though there's no real need for it):
<pre class="verbatim"># Instead of stdout "Hello" !write;
true write stdout "Hello" !act;
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