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</pre></div><pre class="rust"><code><span class="doccomment">/// `pub mod calculator;` is a Rust code snippet that declares a module named `calculator` and makes it
/// public (`pub`). This means that the contents of the `calculator` module can be accessed from outside
/// the current module or crate.
</span><span class="kw">pub mod </span>calculator;
<span class="attr">#[cfg(test)]
</span><span class="doccomment">/// The `pub mod tests { ... }` block in Rust is defining a module named `tests` that is also made
/// public (`pub`). Within this module, there is a test function defined using the `#[test]` attribute,
/// which indicates that this function is a test that should be run by the test harness.
</span><span class="kw">pub mod </span>tests {
<span class="kw">use super</span>::<span class="kw-2">*</span>;
<span class="attr">#[test]
</span><span class="doccomment">/// The function `test_calculator` tests the addition operation of a calculator module in Rust.
</span><span class="kw">fn </span>test_calculator() {
<span class="kw">let </span>value = calculator::try_add(<span class="number">10</span>, <span class="number">20</span>);
<span class="kw">let </span><span class="kw-2">mut </span>value_add = <span class="number">0</span>;
<span class="kw">match </span>value {
<span class="prelude-val">Some</span>(value) => value_add = value,
<span class="prelude-val">None </span>=> <span class="macro">println!</span>(<span class="string">"Invalid value"</span>)
}
<span class="macro">assert_eq!</span>(value_add, <span class="number">30</span>, <span class="string">"Invalid value"</span>);
}
} </code></pre></div></section></main></body></html>