<!DOCTYPE HTML> <html lang="en" class="sidebar-visible no-js"> <head> <!-- Book generated using mdBook --> <meta charset="UTF-8"> <title>Referring to Names in Different Modules - The Rust Programming Language</title> <meta content="text/html; charset=utf-8" http-equiv="Content-Type"> <meta name="description" content=""> <meta name="viewport" content="width=device-width, initial-scale=1"> <meta name="theme-color" content="#ffffff" /> <base href=""> <link rel="stylesheet" href="book.css"> <link href="https://fonts.googleapis.com/css?family=Open+Sans:300italic,400italic,600italic,700italic,800italic,400,300,600,700,800" rel="stylesheet" type="text/css"> <link href="https://fonts.googleapis.com/css?family=Source+Code+Pro:500" rel="stylesheet" type="text/css"> <link rel="shortcut icon" href="favicon.png"> <!-- Font Awesome --> <link rel="stylesheet" href="_FontAwesome/css/font-awesome.css"> <link rel="stylesheet" href="highlight.css"> <link rel="stylesheet" href="tomorrow-night.css"> <link 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displayed --> <script type="text/javascript"> var html = document.querySelector('html'); var sidebar = 'hidden'; if (document.body.clientWidth >= 1080) { try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { } sidebar = sidebar || 'visible'; } html.classList.remove('sidebar-visible'); html.classList.add("sidebar-" + sidebar); </script> <nav id="sidebar" class="sidebar" aria-label="Table of contents"> <ol class="chapter"><li class="affix"><a href="foreword.html">Foreword</a></li><li class="affix"><a href="ch00-00-introduction.html">Introduction</a></li><li><a href="ch01-00-getting-started.html"><strong aria-hidden="true">1.</strong> Getting Started</a></li><li><ol class="section"><li><a href="ch01-01-installation.html"><strong aria-hidden="true">1.1.</strong> Installation</a></li><li><a href="ch01-02-hello-world.html"><strong aria-hidden="true">1.2.</strong> Hello, World!</a></li><li><a href="ch01-03-hello-cargo.html"><strong aria-hidden="true">1.3.</strong> Hello, Cargo!</a></li></ol></li><li><a href="ch02-00-guessing-game-tutorial.html"><strong aria-hidden="true">2.</strong> Programming a Guessing Game</a></li><li><a href="ch03-00-common-programming-concepts.html"><strong aria-hidden="true">3.</strong> Common Programming Concepts</a></li><li><ol class="section"><li><a href="ch03-01-variables-and-mutability.html"><strong aria-hidden="true">3.1.</strong> Variables and Mutability</a></li><li><a href="ch03-02-data-types.html"><strong aria-hidden="true">3.2.</strong> Data Types</a></li><li><a href="ch03-03-how-functions-work.html"><strong aria-hidden="true">3.3.</strong> How Functions Work</a></li><li><a href="ch03-04-comments.html"><strong aria-hidden="true">3.4.</strong> Comments</a></li><li><a href="ch03-05-control-flow.html"><strong aria-hidden="true">3.5.</strong> Control Flow</a></li></ol></li><li><a href="ch04-00-understanding-ownership.html"><strong aria-hidden="true">4.</strong> Understanding Ownership</a></li><li><ol class="section"><li><a href="ch04-01-what-is-ownership.html"><strong aria-hidden="true">4.1.</strong> What is Ownership?</a></li><li><a href="ch04-02-references-and-borrowing.html"><strong aria-hidden="true">4.2.</strong> References & Borrowing</a></li><li><a href="ch04-03-slices.html"><strong aria-hidden="true">4.3.</strong> Slices</a></li></ol></li><li><a href="ch05-00-structs.html"><strong aria-hidden="true">5.</strong> Using Structs to Structure Related Data</a></li><li><ol class="section"><li><a href="ch05-01-defining-structs.html"><strong aria-hidden="true">5.1.</strong> Defining and Instantiating Structs</a></li><li><a href="ch05-02-example-structs.html"><strong aria-hidden="true">5.2.</strong> An Example Program Using Structs</a></li><li><a href="ch05-03-method-syntax.html"><strong aria-hidden="true">5.3.</strong> Method Syntax</a></li></ol></li><li><a href="ch06-00-enums.html"><strong aria-hidden="true">6.</strong> Enums and Pattern Matching</a></li><li><ol class="section"><li><a href="ch06-01-defining-an-enum.html"><strong aria-hidden="true">6.1.</strong> Defining an Enum</a></li><li><a href="ch06-02-match.html"><strong aria-hidden="true">6.2.</strong> The match Control Flow Operator</a></li><li><a href="ch06-03-if-let.html"><strong aria-hidden="true">6.3.</strong> Concise Control Flow with if let</a></li></ol></li><li><a href="ch07-00-modules.html"><strong aria-hidden="true">7.</strong> Modules</a></li><li><ol class="section"><li><a href="ch07-01-mod-and-the-filesystem.html"><strong aria-hidden="true">7.1.</strong> mod and the Filesystem</a></li><li><a href="ch07-02-controlling-visibility-with-pub.html"><strong aria-hidden="true">7.2.</strong> Controlling Visibility with pub</a></li><li><a href="ch07-03-importing-names-with-use.html" class="active"><strong aria-hidden="true">7.3.</strong> Referring to Names in Different Modules</a></li></ol></li><li><a href="ch08-00-common-collections.html"><strong aria-hidden="true">8.</strong> Common Collections</a></li><li><ol class="section"><li><a href="ch08-01-vectors.html"><strong aria-hidden="true">8.1.</strong> Vectors</a></li><li><a href="ch08-02-strings.html"><strong aria-hidden="true">8.2.</strong> Strings</a></li><li><a href="ch08-03-hash-maps.html"><strong aria-hidden="true">8.3.</strong> Hash Maps</a></li></ol></li><li><a href="ch09-00-error-handling.html"><strong aria-hidden="true">9.</strong> Error Handling</a></li><li><ol class="section"><li><a href="ch09-01-unrecoverable-errors-with-panic.html"><strong aria-hidden="true">9.1.</strong> Unrecoverable Errors with panic!</a></li><li><a href="ch09-02-recoverable-errors-with-result.html"><strong aria-hidden="true">9.2.</strong> Recoverable Errors with Result</a></li><li><a href="ch09-03-to-panic-or-not-to-panic.html"><strong aria-hidden="true">9.3.</strong> To panic! or Not To panic!</a></li></ol></li><li><a href="ch10-00-generics.html"><strong aria-hidden="true">10.</strong> Generic Types, Traits, and Lifetimes</a></li><li><ol class="section"><li><a href="ch10-01-syntax.html"><strong aria-hidden="true">10.1.</strong> Generic Data Types</a></li><li><a href="ch10-02-traits.html"><strong aria-hidden="true">10.2.</strong> Traits: Defining Shared Behavior</a></li><li><a href="ch10-03-lifetime-syntax.html"><strong aria-hidden="true">10.3.</strong> Validating References with Lifetimes</a></li></ol></li><li><a href="ch11-00-testing.html"><strong aria-hidden="true">11.</strong> Testing</a></li><li><ol class="section"><li><a href="ch11-01-writing-tests.html"><strong aria-hidden="true">11.1.</strong> Writing tests</a></li><li><a href="ch11-02-running-tests.html"><strong aria-hidden="true">11.2.</strong> Running tests</a></li><li><a href="ch11-03-test-organization.html"><strong aria-hidden="true">11.3.</strong> Test Organization</a></li></ol></li><li><a href="ch12-00-an-io-project.html"><strong aria-hidden="true">12.</strong> An I/O Project: Building a Command Line Program</a></li><li><ol class="section"><li><a href="ch12-01-accepting-command-line-arguments.html"><strong aria-hidden="true">12.1.</strong> Accepting Command Line Arguments</a></li><li><a href="ch12-02-reading-a-file.html"><strong aria-hidden="true">12.2.</strong> Reading a File</a></li><li><a href="ch12-03-improving-error-handling-and-modularity.html"><strong aria-hidden="true">12.3.</strong> Refactoring to Improve Modularity and Error Handling</a></li><li><a href="ch12-04-testing-the-librarys-functionality.html"><strong aria-hidden="true">12.4.</strong> Developing the Library’s Functionality with Test Driven Development</a></li><li><a href="ch12-05-working-with-environment-variables.html"><strong aria-hidden="true">12.5.</strong> Working with Environment Variables</a></li><li><a href="ch12-06-writing-to-stderr-instead-of-stdout.html"><strong aria-hidden="true">12.6.</strong> Writing Error Messages to Standard Error Instead of Standard Output</a></li></ol></li><li><a href="ch13-00-functional-features.html"><strong aria-hidden="true">13.</strong> Functional Language Features: Iterators and Closures</a></li><li><ol class="section"><li><a href="ch13-01-closures.html"><strong aria-hidden="true">13.1.</strong> Closures: Anonymous Functions that Can Capture Their Environment</a></li><li><a href="ch13-02-iterators.html"><strong aria-hidden="true">13.2.</strong> Processing a Series of Items with Iterators</a></li><li><a href="ch13-03-improving-our-io-project.html"><strong aria-hidden="true">13.3.</strong> Improving Our I/O Project</a></li><li><a href="ch13-04-performance.html"><strong aria-hidden="true">13.4.</strong> Comparing Performance: Loops vs. Iterators</a></li></ol></li><li><a href="ch14-00-more-about-cargo.html"><strong aria-hidden="true">14.</strong> More about Cargo and Crates.io</a></li><li><ol class="section"><li><a href="ch14-01-release-profiles.html"><strong aria-hidden="true">14.1.</strong> Customizing Builds with Release Profiles</a></li><li><a href="ch14-02-publishing-to-crates-io.html"><strong aria-hidden="true">14.2.</strong> Publishing a Crate to Crates.io</a></li><li><a href="ch14-03-cargo-workspaces.html"><strong aria-hidden="true">14.3.</strong> Cargo Workspaces</a></li><li><a href="ch14-04-installing-binaries.html"><strong aria-hidden="true">14.4.</strong> Installing Binaries from Crates.io with cargo install</a></li><li><a href="ch14-05-extending-cargo.html"><strong aria-hidden="true">14.5.</strong> Extending Cargo with Custom Commands</a></li></ol></li><li><a href="ch15-00-smart-pointers.html"><strong aria-hidden="true">15.</strong> Smart Pointers</a></li><li><ol class="section"><li><a href="ch15-01-box.html"><strong aria-hidden="true">15.1.</strong> Box<T> Points to Data on the Heap and Has a Known Size</a></li><li><a href="ch15-02-deref.html"><strong aria-hidden="true">15.2.</strong> The Deref Trait Allows Access to the Data Through a Reference</a></li><li><a href="ch15-03-drop.html"><strong aria-hidden="true">15.3.</strong> The Drop Trait Runs Code on Cleanup</a></li><li><a href="ch15-04-rc.html"><strong aria-hidden="true">15.4.</strong> Rc<T>, the Reference Counted Smart Pointer</a></li><li><a href="ch15-05-interior-mutability.html"><strong aria-hidden="true">15.5.</strong> RefCell<T> and the Interior Mutability Pattern</a></li><li><a href="ch15-06-reference-cycles.html"><strong aria-hidden="true">15.6.</strong> Creating Reference Cycles and Leaking Memory is Safe</a></li></ol></li><li><a href="ch16-00-concurrency.html"><strong aria-hidden="true">16.</strong> Fearless Concurrency</a></li><li><ol class="section"><li><a href="ch16-01-threads.html"><strong aria-hidden="true">16.1.</strong> Threads</a></li><li><a href="ch16-02-message-passing.html"><strong aria-hidden="true">16.2.</strong> Message Passing</a></li><li><a href="ch16-03-shared-state.html"><strong aria-hidden="true">16.3.</strong> Shared State</a></li><li><a href="ch16-04-extensible-concurrency-sync-and-send.html"><strong aria-hidden="true">16.4.</strong> Extensible Concurrency: Sync and Send</a></li></ol></li><li><a href="ch17-00-oop.html"><strong aria-hidden="true">17.</strong> Object Oriented Programming Features of Rust</a></li><li><ol class="section"><li><a href="ch17-01-what-is-oo.html"><strong aria-hidden="true">17.1.</strong> Characteristics of Object-Oriented Languages</a></li><li><a href="ch17-02-trait-objects.html"><strong aria-hidden="true">17.2.</strong> Using Trait Objects that Allow for Values of Different Types</a></li><li><a href="ch17-03-oo-design-patterns.html"><strong aria-hidden="true">17.3.</strong> Implementing an Object-Oriented Design Pattern</a></li></ol></li><li><a href="ch18-00-patterns.html"><strong aria-hidden="true">18.</strong> Patterns Match the Structure of Values</a></li><li><ol class="section"><li><a href="ch18-01-all-the-places-for-patterns.html"><strong aria-hidden="true">18.1.</strong> All the Places Patterns May be Used</a></li><li><a href="ch18-02-refutability.html"><strong aria-hidden="true">18.2.</strong> Refutability: Whether a Pattern Might Fail to Match</a></li><li><a href="ch18-03-pattern-syntax.html"><strong aria-hidden="true">18.3.</strong> All the Pattern Syntax</a></li></ol></li><li><a href="ch19-00-advanced-features.html"><strong aria-hidden="true">19.</strong> Advanced Features</a></li><li><ol class="section"><li><a href="ch19-01-unsafe-rust.html"><strong aria-hidden="true">19.1.</strong> Unsafe Rust</a></li><li><a href="ch19-02-advanced-lifetimes.html"><strong aria-hidden="true">19.2.</strong> Advanced Lifetimes</a></li><li><a href="ch19-03-advanced-traits.html"><strong aria-hidden="true">19.3.</strong> Advanced Traits</a></li><li><a href="ch19-04-advanced-types.html"><strong aria-hidden="true">19.4.</strong> Advanced Types</a></li><li><a href="ch19-05-advanced-functions-and-closures.html"><strong aria-hidden="true">19.5.</strong> Advanced Functions & Closures</a></li></ol></li><li><a href="ch20-00-final-project-a-web-server.html"><strong aria-hidden="true">20.</strong> Final Project: Building a Multithreaded Web Server</a></li><li><ol class="section"><li><a href="ch20-01-single-threaded.html"><strong aria-hidden="true">20.1.</strong> A Single Threaded Web Server</a></li><li><a href="ch20-02-multithreaded.html"><strong aria-hidden="true">20.2.</strong> Turning our Single Threaded Server into a Multithreaded Server</a></li><li><a href="ch20-03-graceful-shutdown-and-cleanup.html"><strong aria-hidden="true">20.3.</strong> Graceful Shutdown and Cleanup</a></li></ol></li><li><a href="appendix-00.html"><strong aria-hidden="true">21.</strong> Appendix</a></li><li><ol class="section"><li><a href="appendix-01-keywords.html"><strong aria-hidden="true">21.1.</strong> A - Keywords</a></li><li><a href="appendix-02-operators.html"><strong aria-hidden="true">21.2.</strong> B - Operators and Symbols</a></li><li><a href="appendix-03-derivable-traits.html"><strong aria-hidden="true">21.3.</strong> C - Derivable Traits</a></li><li><a href="appendix-04-macros.html"><strong aria-hidden="true">21.4.</strong> D - Macros</a></li><li><a href="appendix-05-translation.html"><strong aria-hidden="true">21.5.</strong> E - Translations</a></li><li><a href="appendix-06-newest-features.html"><strong aria-hidden="true">21.6.</strong> F - Newest Features</a></li><li><a href="appendix-07-nightly-rust.html"><strong aria-hidden="true">21.7.</strong> G - How Rust is Made and “Nightly Rust”</a></li></ol></li></ol> </nav> <div id="page-wrapper" class="page-wrapper"> <div class="page"> <div id="menu-bar" class="menu-bar"> <div id="menu-bar-sticky-container"> <div class="left-buttons"> <button id="sidebar-toggle" class="icon-button" type="button" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar"> <i class="fa fa-bars"></i> </button> <button id="theme-toggle" class="icon-button" 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(Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar"> <i class="fa fa-search"></i> </button> </div> <h1 class="menu-title">The Rust Programming Language</h1> <div class="right-buttons"> <a href="print.html" title="Print this book" aria-label="Print this book"> <i id="print-button" class="fa fa-print"></i> </a> </div> </div> </div> <div id="search-wrapper" class="hidden"> <form id="searchbar-outer" class="searchbar-outer"> <input type="search" name="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header"> </form> <div id="searchresults-outer" class="searchresults-outer hidden"> <div id="searchresults-header" class="searchresults-header"></div> <ul id="searchresults"> </ul> </div> </div> <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM --> <script type="text/javascript"> document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible'); document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible'); Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) { link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1); }); </script> <div id="content" class="content"> <main> <a class="header" href="ch07-03-importing-names-with-use.html#referring-to-names-in-different-modules" id="referring-to-names-in-different-modules"><h2>Referring to Names in Different Modules</h2></a> <p>We’ve covered how to call functions defined within a module using the module name as part of the call, as in the call to the <code>nested_modules</code> function shown here in Listing 7-7:</p> <p><span class="filename">Filename: src/main.rs</span></p> <pre><pre class="playpen"><code class="language-rust">pub mod a { pub mod series { pub mod of { pub fn nested_modules() {} } } } fn main() { a::series::of::nested_modules(); } </code></pre></pre> <p><span class="caption">Listing 7-7: Calling a function by fully specifying its enclosing module’s path</span></p> <p>As you can see, referring to the fully qualified name can get quite lengthy. Fortunately, Rust has a keyword to make these calls more concise.</p> <a class="header" href="ch07-03-importing-names-with-use.html#bringing-names-into-scope-with-the-use-keyword" id="bringing-names-into-scope-with-the-use-keyword"><h3>Bringing Names into Scope with the <code>use</code> Keyword</h3></a> <p>Rust’s <code>use</code> keyword shortens lengthy function calls by bringing the modules of the function you want to call into scope. Here’s an example of bringing the <code>a::series::of</code> module into a binary crate’s root scope:</p> <p><span class="filename">Filename: src/main.rs</span></p> <pre><pre class="playpen"><code class="language-rust">pub mod a { pub mod series { pub mod of { pub fn nested_modules() {} } } } use a::series::of; fn main() { of::nested_modules(); } </code></pre></pre> <p>The line <code>use a::series::of;</code> means that rather than using the full <code>a::series::of</code> path wherever we want to refer to the <code>of</code> module, we can use <code>of</code>.</p> <p>The <code>use</code> keyword brings only what we’ve specified into scope: it does not bring children of modules into scope. That’s why we still have to use <code>of::nested_modules</code> when we want to call the <code>nested_modules</code> function.</p> <p>We could have chosen to bring the function into scope by instead specifying the function in the <code>use</code> as follows:</p> <pre><pre class="playpen"><code class="language-rust">pub mod a { pub mod series { pub mod of { pub fn nested_modules() {} } } } use a::series::of::nested_modules; fn main() { nested_modules(); } </code></pre></pre> <p>Doing so allows us to exclude all the modules and reference the function directly.</p> <p>Because enums also form a sort of namespace like modules, we can bring an enum’s variants into scope with <code>use</code> as well. For any kind of <code>use</code> statement, if you’re bringing multiple items from one namespace into scope, you can list them using curly brackets and commas in the last position, like so:</p> <pre><pre class="playpen"><code class="language-rust">enum TrafficLight { Red, Yellow, Green, } use TrafficLight::{Red, Yellow}; fn main() { let red = Red; let yellow = Yellow; let green = TrafficLight::Green; } </code></pre></pre> <p>We’re still specifying the <code>TrafficLight</code> namespace for the <code>Green</code> variant because we didn’t include <code>Green</code> in the <code>use</code> statement.</p> <a class="header" href="ch07-03-importing-names-with-use.html#bringing-all-names-into-scope-with-a-glob" id="bringing-all-names-into-scope-with-a-glob"><h3>Bringing All Names into Scope with a Glob</h3></a> <p>To bring all the items in a namespace into scope at once, we can use the <code>*</code> syntax, which is called the <em>glob operator</em>. This example brings all the variants of an enum into scope without having to list each specifically:</p> <pre><pre class="playpen"><code class="language-rust">enum TrafficLight { Red, Yellow, Green, } use TrafficLight::*; fn main() { let red = Red; let yellow = Yellow; let green = Green; } </code></pre></pre> <p>The <code>*</code> will bring into scope all the visible items in the <code>TrafficLight</code> namespace. You should use globs sparingly: they are convenient, but a glob might also pull in more items than you expected and cause naming conflicts.</p> <a class="header" href="ch07-03-importing-names-with-use.html#using-super-to-access-a-parent-module" id="using-super-to-access-a-parent-module"><h3>Using <code>super</code> to Access a Parent Module</h3></a> <p>As you saw at the beginning of this chapter, when you create a library crate, Cargo makes a <code>tests</code> module for you. Let’s go into more detail about that now. In your <code>communicator</code> project, open <em>src/lib.rs</em>:</p> <p><span class="filename">Filename: src/lib.rs</span></p> <pre><code class="language-rust ignore">pub mod client; pub mod network; #[cfg(test)] mod tests { #[test] fn it_works() { assert_eq!(2 + 2, 4); } } </code></pre> <p>Chapter 11 explains more about testing, but parts of this example should make sense now: we have a module named <code>tests</code> that lives next to our other modules and contains one function named <code>it_works</code>. Even though there are special annotations, the <code>tests</code> module is just another module! So our module hierarchy looks like this:</p> <pre><code class="language-text">communicator ├── client ├── network | └── client └── tests </code></pre> <p>Tests are for exercising the code within our library, so let’s try to call our <code>client::connect</code> function from this <code>it_works</code> function, even though we won’t be checking any functionality right now. This won’t work yet:</p> <p><span class="filename">Filename: src/lib.rs</span></p> <pre><pre class="playpen"><code class="language-rust"> # #![allow(unused_variables)] #fn main() { #[cfg(test)] mod tests { #[test] fn it_works() { client::connect(); } } #}</code></pre></pre> <p>Run the tests by invoking the <code>cargo test</code> command:</p> <pre><code class="language-text">$ cargo test Compiling communicator v0.1.0 (file:///projects/communicator) error[E0433]: failed to resolve. Use of undeclared type or module `client` --> src/lib.rs:9:9 | 9 | client::connect(); | ^^^^^^ Use of undeclared type or module `client` </code></pre> <p>The compilation failed, but why? We don’t need to place <code>communicator::</code> in front of the function, as we did in <em>src/main.rs</em>, because we are definitely within the <code>communicator</code> library crate here. The reason is that paths are always relative to the current module, which here is <code>tests</code>. The only exception is in a <code>use</code> statement, where paths are relative to the crate root by default. Our <code>tests</code> module needs the <code>client</code> module in its scope!</p> <p>So how do we get back up one module in the module hierarchy to call the <code>client::connect</code> function in the <code>tests</code> module? In the <code>tests</code> module, we can either use leading colons to let Rust know that we want to start from the root and list the whole path, like this:</p> <pre><code class="language-rust ignore">::client::connect(); </code></pre> <p>Or, we can use <code>super</code> to move up one module in the hierarchy from our current module, like this:</p> <pre><code class="language-rust ignore">super::client::connect(); </code></pre> <p>These two options don’t look that different in this example, but if you’re deeper in a module hierarchy, starting from the root every time would make your code lengthy. In those cases, using <code>super</code> to get from the current module to sibling modules is a good shortcut. Plus, if you’ve specified the path from the root in many places in your code and then rearrange your modules by moving a subtree to another place, you’ll end up needing to update the path in several places, which would be tedious.</p> <p>It would also be annoying to have to type <code>super::</code> in each test, but you’ve already seen the tool for that solution: <code>use</code>! The <code>super::</code> functionality changes the path you give to <code>use</code> so it is relative to the parent module instead of to the root module.</p> <p>For these reasons, in the <code>tests</code> module especially, <code>use super::something</code> is usually the best solution. So now our test looks like this:</p> <p><span class="filename">Filename: src/lib.rs</span></p> <pre><pre class="playpen"><code class="language-rust"> # #![allow(unused_variables)] #fn main() { #[cfg(test)] mod tests { use super::client; #[test] fn it_works() { client::connect(); } } #}</code></pre></pre> <p>When we run <code>cargo test</code> again, the test will pass, and the first part of the test result output will be the following:</p> <pre><code class="language-text">$ cargo test Compiling communicator v0.1.0 (file:///projects/communicator) Running target/debug/communicator-92007ddb5330fa5a running 1 test test tests::it_works ... ok test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out </code></pre> <a class="header" href="ch07-03-importing-names-with-use.html#summary" id="summary"><h2>Summary</h2></a> <p>Now you know some new techniques for organizing your code! Use these techniques to group related functionality together, keep files from becoming too long, and present a tidy public API to your library users.</p> <p>Next, we’ll look at some collection data structures in the standard library that you can use in your nice, neat code.</p> </main> <nav class="nav-wrapper" aria-label="Page navigation"> <!-- Mobile navigation buttons --> <a rel="prev" href="ch07-02-controlling-visibility-with-pub.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left"> <i class="fa fa-angle-left"></i> </a> <a rel="next" href="ch08-00-common-collections.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right"> <i class="fa fa-angle-right"></i> </a> <div style="clear: both"></div> </nav> </div> </div> <nav class="nav-wide-wrapper" aria-label="Page navigation"> <a href="ch07-02-controlling-visibility-with-pub.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left"> <i class="fa fa-angle-left"></i> </a> <a href="ch08-00-common-collections.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right"> <i class="fa fa-angle-right"></i> </a> </nav> </div> <script src="searchindex.js" type="text/javascript" charset="utf-8"></script> <script src="elasticlunr.min.js" type="text/javascript" charset="utf-8"></script> <script src="mark.min.js" type="text/javascript" charset="utf-8"></script> <script src="searcher.js" type="text/javascript" charset="utf-8"></script> <script src="clipboard.min.js" type="text/javascript" charset="utf-8"></script> <script src="highlight.js" type="text/javascript" charset="utf-8"></script> <script src="book.js" type="text/javascript" charset="utf-8"></script> <!-- Custom JS scripts --> </body> </html>