.html">view current version</a>.
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<div id="functions-programming.chapter" class="section level1">
<h1 number="18"><span class="header-section-number">18</span> User-Defined Functions</h1>
<p>This chapter explains functions from a user perspective with examples;
see the language reference for a full specification. User-defined
functions allow computations to be encapsulated into a single named
unit and invoked elsewhere by name. Similarly, functions allow
complex procedures to be broken down into more 