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<h3 class="section">2.1 Operators</h3>
<p><a name="index-operators-2"></a>Enigma has 4 operators: <code>!</code>, <code>=</code>, <code>|</code>, and
<code>*</code>. <code>!</code> and <code>=</code> are the most important ones.
<p>To assign values to variables, use the <code>=</code> operator. For example:
<pre class="verbatim">obj = hello-string;
</pre>
Here, the variable <code>hello-string</code> receives the object <code>obj</code>. Note
the syntax. The objects comes first. Unless <code>hello-string</code> is
already defined, it is created as a local variable.
<p>Now, say we have a function called <code>think</code> and we want to send
objects to it. This is how that's done:
<pre class="verbatim">obj1 obj2 obj3 ! think;
</pre>
<p>There are no limits to the amount of objects that can be sent to a
function. Whitespace characters are used to separate objects, also when
assigning them to a variable. There <em>is</em> a difference between
using one object and more objects as arguments, though. When using only
one object, that object is simply used, but when using more objects, a
list containing all objects is created and transmitted instead. So, in
reality, when assigning two or more objects to a variable, the variable
points to a list with the objects. More about lists later.
<p>The <code>|</code> operator is merely a shortcut operator. It can merge
several commands into one, long command. See the following example:
<pre class="verbatim"># Long version
a ! b = c;
d c ! e = c;
# Short version
a ! b | d temp ! e = c;
</pre>
<p>Here, <code>a</code> is sent to <code>b</code>, which is then &mdash; together with
<code>d</code> &mdash; sent to <code>e</code> and saved in <code>c</code>. The <code>|</code> acts
like the semicolon, but it copies the return value of the last function
(in this case <code>b</code>) and stores the value in the local variable
<code>temp</code>. Hackers are encouraged to use this operator.
<p>The final operator, <code>*</code>, has the same function as <code>=</code>, except
that it works on a global level. So, if the code is <code>b = a;</code> and
<code>a</code> does not exist, it is created &mdash; in the global space.
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