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<p>
Gleam lacks exceptions, macros, type classes, early returns, and a variety of
other features, instead going all-in with just first-class-functions and
pattern matching. This makes Gleam code easier to understand, but it can
sometimes result in excessive indentation.
</p>
<p>
Gleam's use expression helps out here by enabling us to write code that uses
callbacks in an unindented style, as shown in the code window.
</p>
<p>
The higher order function being called goes on the right hand side of the
<code><-</code> operator. It must take a callback function as its final
argument.
</p>
<p>
The argument names for the callback function go on the left hand side of the
<code><-</code> operator. The function can take any number of arguments,
including zero.
</p>
<p>
All the remaining code in the enclosing <code class="hljs">{}</code> block
becomes the body of the callback function.
</p>
<p>
This is a very capable and useful feature, but excessive application of
<code>use</code> may result in unclear code, especially to beginners. Usually
the regular function call syntax results in more approachable code!
</p>
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