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<ol class="chapter"><li class="chapter-item affix "><a href="../index.html">Introduction</a></li><li class="chapter-item "><a href="../hello.html"><strong aria-hidden="true">1.</strong> Hello World</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../hello/comment.html"><strong aria-hidden="true">1.1.</strong> Comments</a></li><li class="chapter-item "><a href="../hello/print.html"><strong aria-hidden="true">1.2.</strong> Formatted print</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../hello/print/print_debug.html"><strong aria-hidden="true">1.2.1.</strong> Debug</a></li><li class="chapter-item "><a href="../hello/print/print_display.html"><strong aria-hidden="true">1.2.2.</strong> Display</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../hello/print/print_display/testcase_list.html"><strong aria-hidden="true">1.2.2.1.</strong> Testcase: List</a></li></ol></li><li class="chapter-item "><a href="../hello/print/fmt.html"><strong aria-hidden="true">1.2.3.</strong> Formatting</a></li></ol></li></ol></li><li class="chapter-item "><a href="../primitives.html"><strong aria-hidden="true">2.</strong> Primitives</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../primitives/literals.html"><strong aria-hidden="true">2.1.</strong> Literals and operators</a></li><li class="chapter-item "><a href="../primitives/tuples.html"><strong aria-hidden="true">2.2.</strong> Tuples</a></li><li class="chapter-item "><a href="../primitives/array.html"><strong aria-hidden="true">2.3.</strong> Arrays and Slices</a></li></ol></li><li class="chapter-item "><a href="../custom_types.html"><strong aria-hidden="true">3.</strong> Custom Types</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../custom_types/structs.html"><strong aria-hidden="true">3.1.</strong> Structures</a></li><li class="chapter-item "><a href="../custom_types/enum.html"><strong aria-hidden="true">3.2.</strong> Enums</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../custom_types/enum/enum_use.html"><strong aria-hidden="true">3.2.1.</strong> use</a></li><li class="chapter-item "><a href="../custom_types/enum/c_like.html"><strong aria-hidden="true">3.2.2.</strong> C-like</a></li><li class="chapter-item "><a href="../custom_types/enum/testcase_linked_list.html"><strong aria-hidden="true">3.2.3.</strong> Testcase: linked-list</a></li></ol></li><li class="chapter-item "><a href="../custom_types/constants.html"><strong aria-hidden="true">3.3.</strong> constants</a></li></ol></li><li class="chapter-item "><a href="../variable_bindings.html"><strong aria-hidden="true">4.</strong> Variable Bindings</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../variable_bindings/mut.html"><strong aria-hidden="true">4.1.</strong> Mutability</a></li><li class="chapter-item "><a href="../variable_bindings/scope.html"><strong aria-hidden="true">4.2.</strong> Scope and Shadowing</a></li><li class="chapter-item "><a href="../variable_bindings/declare.html"><strong aria-hidden="true">4.3.</strong> Declare first</a></li><li class="chapter-item "><a href="../variable_bindings/freeze.html"><strong aria-hidden="true">4.4.</strong> Freezing</a></li></ol></li><li class="chapter-item "><a href="../types.html"><strong aria-hidden="true">5.</strong> Types</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../types/cast.html"><strong aria-hidden="true">5.1.</strong> Casting</a></li><li class="chapter-item "><a href="../types/literals.html"><strong aria-hidden="true">5.2.</strong> Literals</a></li><li class="chapter-item "><a href="../types/inference.html"><strong aria-hidden="true">5.3.</strong> Inference</a></li><li class="chapter-item "><a href="../types/alias.html"><strong aria-hidden="true">5.4.</strong> Aliasing</a></li></ol></li><li class="chapter-item "><a href="../conversion.html"><strong aria-hidden="true">6.</strong> Conversion</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../conversion/from_into.html"><strong aria-hidden="true">6.1.</strong> From and Into</a></li><li class="chapter-item "><a href="../conversion/try_from_try_into.html"><strong aria-hidden="true">6.2.</strong> TryFrom and TryInto</a></li><li class="chapter-item "><a href="../conversion/string.html"><strong aria-hidden="true">6.3.</strong> To and from Strings</a></li></ol></li><li class="chapter-item "><a href="../expression.html"><strong aria-hidden="true">7.</strong> Expressions</a></li><li class="chapter-item "><a href="../flow_control.html"><strong aria-hidden="true">8.</strong> Flow of Control</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../flow_control/if_else.html"><strong aria-hidden="true">8.1.</strong> if/else</a></li><li class="chapter-item "><a href="../flow_control/loop.html"><strong aria-hidden="true">8.2.</strong> loop</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../flow_control/loop/nested.html"><strong aria-hidden="true">8.2.1.</strong> Nesting and labels</a></li><li class="chapter-item "><a href="../flow_control/loop/return.html"><strong aria-hidden="true">8.2.2.</strong> Returning from loops</a></li></ol></li><li class="chapter-item "><a href="../flow_control/while.html"><strong aria-hidden="true">8.3.</strong> while</a></li><li class="chapter-item "><a href="../flow_control/for.html"><strong aria-hidden="true">8.4.</strong> for and range</a></li><li class="chapter-item "><a href="../flow_control/match.html"><strong aria-hidden="true">8.5.</strong> match</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../flow_control/match/destructuring.html"><strong aria-hidden="true">8.5.1.</strong> Destructuring</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../flow_control/match/destructuring/destructure_tuple.html"><strong aria-hidden="true">8.5.1.1.</strong> tuples</a></li><li class="chapter-item "><a href="../flow_control/match/destructuring/destructure_enum.html"><strong aria-hidden="true">8.5.1.2.</strong> enums</a></li><li class="chapter-item "><a href="../flow_control/match/destructuring/destructure_pointers.html"><strong aria-hidden="true">8.5.1.3.</strong> pointers/ref</a></li><li class="chapter-item "><a href="../flow_control/match/destructuring/destructure_structures.html"><strong aria-hidden="true">8.5.1.4.</strong> structs</a></li></ol></li><li class="chapter-item "><a href="../flow_control/match/guard.html"><strong aria-hidden="true">8.5.2.</strong> Guards</a></li><li class="chapter-item "><a href="../flow_control/match/binding.html"><strong aria-hidden="true">8.5.3.</strong> Binding</a></li></ol></li><li class="chapter-item "><a href="../flow_control/if_let.html"><strong aria-hidden="true">8.6.</strong> if let</a></li><li class="chapter-item "><a href="../flow_control/while_let.html"><strong aria-hidden="true">8.7.</strong> while let</a></li></ol></li><li class="chapter-item "><a href="../fn.html"><strong aria-hidden="true">9.</strong> Functions</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../fn/methods.html"><strong aria-hidden="true">9.1.</strong> Methods</a></li><li class="chapter-item "><a href="../fn/closures.html"><strong aria-hidden="true">9.2.</strong> Closures</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../fn/closures/capture.html"><strong aria-hidden="true">9.2.1.</strong> Capturing</a></li><li class="chapter-item "><a href="../fn/closures/input_parameters.html"><strong aria-hidden="true">9.2.2.</strong> As input parameters</a></li><li class="chapter-item "><a href="../fn/closures/anonymity.html"><strong aria-hidden="true">9.2.3.</strong> Type anonymity</a></li><li class="chapter-item "><a href="../fn/closures/input_functions.html"><strong aria-hidden="true">9.2.4.</strong> Input functions</a></li><li class="chapter-item "><a href="../fn/closures/output_parameters.html"><strong aria-hidden="true">9.2.5.</strong> As output parameters</a></li><li class="chapter-item "><a href="../fn/closures/closure_examples.html"><strong aria-hidden="true">9.2.6.</strong> Examples in std</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../fn/closures/closure_examples/iter_any.html"><strong aria-hidden="true">9.2.6.1.</strong> Iterator::any</a></li><li class="chapter-item "><a href="../fn/closures/closure_examples/iter_find.html"><strong aria-hidden="true">9.2.6.2.</strong> Searching through iterators</a></li></ol></li></ol></li><li class="chapter-item "><a href="../fn/hof.html"><strong aria-hidden="true">9.3.</strong> Higher Order Functions</a></li><li class="chapter-item "><a href="../fn/diverging.html"><strong aria-hidden="true">9.4.</strong> Diverging functions</a></li></ol></li><li class="chapter-item "><a href="../mod.html"><strong aria-hidden="true">10.</strong> Modules</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../mod/visibility.html"><strong aria-hidden="true">10.1.</strong> Visibility</a></li><li class="chapter-item "><a href="../mod/struct_visibility.html"><strong aria-hidden="true">10.2.</strong> Struct visibility</a></li><li class="chapter-item "><a href="../mod/use.html"><strong aria-hidden="true">10.3.</strong> The use declaration</a></li><li class="chapter-item "><a href="../mod/super.html"><strong aria-hidden="true">10.4.</strong> super and self</a></li><li class="chapter-item "><a href="../mod/split.html"><strong aria-hidden="true">10.5.</strong> File hierarchy</a></li></ol></li><li class="chapter-item "><a href="../crates.html"><strong aria-hidden="true">11.</strong> Crates</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../crates/lib.html"><strong aria-hidden="true">11.1.</strong> Creating a Library</a></li><li class="chapter-item "><a href="../crates/using_lib.html"><strong aria-hidden="true">11.2.</strong> Using a Library</a></li></ol></li><li class="chapter-item "><a href="../cargo.html"><strong aria-hidden="true">12.</strong> Cargo</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../cargo/deps.html"><strong aria-hidden="true">12.1.</strong> Dependencies</a></li><li class="chapter-item "><a href="../cargo/conventions.html"><strong aria-hidden="true">12.2.</strong> Conventions</a></li><li class="chapter-item "><a href="../cargo/test.html"><strong aria-hidden="true">12.3.</strong> Tests</a></li><li class="chapter-item "><a href="../cargo/build_scripts.html"><strong aria-hidden="true">12.4.</strong> Build Scripts</a></li></ol></li><li class="chapter-item "><a href="../attribute.html"><strong aria-hidden="true">13.</strong> Attributes</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../attribute/unused.html"><strong aria-hidden="true">13.1.</strong> dead_code</a></li><li class="chapter-item "><a href="../attribute/crate.html"><strong aria-hidden="true">13.2.</strong> Crates</a></li><li class="chapter-item "><a href="../attribute/cfg.html"><strong aria-hidden="true">13.3.</strong> cfg</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../attribute/cfg/custom.html"><strong aria-hidden="true">13.3.1.</strong> Custom</a></li></ol></li></ol></li><li class="chapter-item "><a href="../generics.html"><strong aria-hidden="true">14.</strong> Generics</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../generics/gen_fn.html"><strong aria-hidden="true">14.1.</strong> Functions</a></li><li class="chapter-item "><a href="../generics/impl.html"><strong aria-hidden="true">14.2.</strong> Implementation</a></li><li class="chapter-item "><a href="../generics/gen_trait.html"><strong aria-hidden="true">14.3.</strong> Traits</a></li><li class="chapter-item "><a href="../generics/bounds.html"><strong aria-hidden="true">14.4.</strong> Bounds</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../generics/bounds/testcase_empty.html"><strong aria-hidden="true">14.4.1.</strong> Testcase: empty bounds</a></li></ol></li><li class="chapter-item "><a href="../generics/multi_bounds.html"><strong aria-hidden="true">14.5.</strong> Multiple bounds</a></li><li class="chapter-item "><a href="../generics/where.html"><strong aria-hidden="true">14.6.</strong> Where clauses</a></li><li class="chapter-item "><a href="../generics/new_types.html"><strong aria-hidden="true">14.7.</strong> New Type Idiom</a></li><li class="chapter-item "><a href="../generics/assoc_items.html"><strong aria-hidden="true">14.8.</strong> Associated items</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../generics/assoc_items/the_problem.html"><strong aria-hidden="true">14.8.1.</strong> The Problem</a></li><li class="chapter-item "><a href="../generics/assoc_items/types.html"><strong aria-hidden="true">14.8.2.</strong> Associated types</a></li></ol></li><li class="chapter-item "><a href="../generics/phantom.html"><strong aria-hidden="true">14.9.</strong> Phantom type parameters</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../generics/phantom/testcase_units.html"><strong aria-hidden="true">14.9.1.</strong> Testcase: unit clarification</a></li></ol></li></ol></li><li class="chapter-item "><a href="../scope.html"><strong aria-hidden="true">15.</strong> Scoping rules</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../scope/raii.html"><strong aria-hidden="true">15.1.</strong> RAII</a></li><li class="chapter-item "><a href="../scope/move.html"><strong aria-hidden="true">15.2.</strong> Ownership and moves</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../scope/move/mut.html"><strong aria-hidden="true">15.2.1.</strong> Mutability</a></li><li class="chapter-item "><a href="../scope/move/partial_move.html"><strong aria-hidden="true">15.2.2.</strong> Partial moves</a></li></ol></li><li class="chapter-item "><a href="../scope/borrow.html"><strong aria-hidden="true">15.3.</strong> Borrowing</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../scope/borrow/mut.html"><strong aria-hidden="true">15.3.1.</strong> Mutability</a></li><li class="chapter-item "><a href="../scope/borrow/alias.html"><strong aria-hidden="true">15.3.2.</strong> Aliasing</a></li><li class="chapter-item "><a href="../scope/borrow/ref.html"><strong aria-hidden="true">15.3.3.</strong> The ref pattern</a></li></ol></li><li class="chapter-item "><a href="../scope/lifetime.html"><strong aria-hidden="true">15.4.</strong> Lifetimes</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../scope/lifetime/explicit.html"><strong aria-hidden="true">15.4.1.</strong> Explicit annotation</a></li><li class="chapter-item "><a href="../scope/lifetime/fn.html"><strong aria-hidden="true">15.4.2.</strong> Functions</a></li><li class="chapter-item "><a href="../scope/lifetime/methods.html"><strong aria-hidden="true">15.4.3.</strong> Methods</a></li><li class="chapter-item "><a href="../scope/lifetime/struct.html"><strong aria-hidden="true">15.4.4.</strong> Structs</a></li><li class="chapter-item "><a href="../scope/lifetime/trait.html"><strong aria-hidden="true">15.4.5.</strong> Traits</a></li><li class="chapter-item "><a href="../scope/lifetime/lifetime_bounds.html"><strong aria-hidden="true">15.4.6.</strong> Bounds</a></li><li class="chapter-item "><a href="../scope/lifetime/lifetime_coercion.html"><strong aria-hidden="true">15.4.7.</strong> Coercion</a></li><li class="chapter-item "><a href="../scope/lifetime/static_lifetime.html"><strong aria-hidden="true">15.4.8.</strong> Static</a></li><li class="chapter-item "><a href="../scope/lifetime/elision.html"><strong aria-hidden="true">15.4.9.</strong> Elision</a></li></ol></li></ol></li><li class="chapter-item "><a href="../trait.html"><strong aria-hidden="true">16.</strong> Traits</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../trait/derive.html"><strong aria-hidden="true">16.1.</strong> Derive</a></li><li class="chapter-item "><a href="../trait/dyn.html"><strong aria-hidden="true">16.2.</strong> Returning Traits with dyn</a></li><li class="chapter-item "><a href="../trait/ops.html"><strong aria-hidden="true">16.3.</strong> Operator Overloading</a></li><li class="chapter-item "><a href="../trait/drop.html"><strong aria-hidden="true">16.4.</strong> Drop</a></li><li class="chapter-item "><a href="../trait/iter.html"><strong aria-hidden="true">16.5.</strong> Iterators</a></li><li class="chapter-item "><a href="../trait/impl_trait.html"><strong aria-hidden="true">16.6.</strong> impl Trait</a></li><li class="chapter-item "><a href="../trait/clone.html"><strong aria-hidden="true">16.7.</strong> Clone</a></li><li class="chapter-item "><a href="../trait/supertraits.html"><strong aria-hidden="true">16.8.</strong> Supertraits</a></li><li class="chapter-item "><a href="../trait/disambiguating.html"><strong aria-hidden="true">16.9.</strong> Disambiguating overlapping traits</a></li></ol></li><li class="chapter-item "><a href="../macros.html"><strong aria-hidden="true">17.</strong> macro_rules!</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../macros/syntax.html"><strong aria-hidden="true">17.1.</strong> Syntax</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../macros/designators.html"><strong aria-hidden="true">17.1.1.</strong> Designators</a></li><li class="chapter-item "><a href="../macros/overload.html"><strong aria-hidden="true">17.1.2.</strong> Overload</a></li><li class="chapter-item "><a href="../macros/repeat.html"><strong aria-hidden="true">17.1.3.</strong> Repeat</a></li></ol></li><li class="chapter-item "><a href="../macros/dry.html"><strong aria-hidden="true">17.2.</strong> DRY (Don't Repeat Yourself)</a></li><li class="chapter-item "><a href="../macros/dsl.html"><strong aria-hidden="true">17.3.</strong> DSL (Domain Specific Languages)</a></li><li class="chapter-item "><a href="../macros/variadics.html"><strong aria-hidden="true">17.4.</strong> Variadics</a></li></ol></li><li class="chapter-item "><a href="../error.html"><strong aria-hidden="true">18.</strong> Error handling</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../error/panic.html"><strong aria-hidden="true">18.1.</strong> panic</a></li><li class="chapter-item "><a href="../error/option_unwrap.html"><strong aria-hidden="true">18.2.</strong> Option &amp; unwrap</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../error/option_unwrap/question_mark.html"><strong aria-hidden="true">18.2.1.</strong> Unpacking options with ?</a></li><li class="chapter-item "><a href="../error/option_unwrap/map.html"><strong aria-hidden="true">18.2.2.</strong> Combinators: map</a></li><li class="chapter-item "><a href="../error/option_unwrap/and_then.html"><strong aria-hidden="true">18.2.3.</strong> Combinators: and_then</a></li></ol></li><li class="chapter-item "><a href="../error/result.html"><strong aria-hidden="true">18.3.</strong> Result</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../error/result/result_map.html"><strong aria-hidden="true">18.3.1.</strong> map for Result</a></li><li class="chapter-item "><a href="../error/result/result_alias.html"><strong aria-hidden="true">18.3.2.</strong> aliases for Result</a></li><li class="chapter-item "><a href="../error/result/early_returns.html"><strong aria-hidden="true">18.3.3.</strong> Early returns</a></li><li class="chapter-item "><a href="../error/result/enter_question_mark.html"><strong aria-hidden="true">18.3.4.</strong> Introducing ?</a></li></ol></li><li class="chapter-item "><a href="../error/multiple_error_types.html"><strong aria-hidden="true">18.4.</strong> Multiple error types</a><a class="toggle"><div></div></a></li><li><ol class="section"><li class="chapter-item "><a href="../error/multiple_error_types/option_result.html"><strong aria-hidden="true">18.4.1.</strong> Pulling Results out of Options</a></li><li class="chapter-item "><a href="../error/multiple_error_types/define_error_type.html"><strong aria-hidden="true">18.4.2.</strong> Defining an error type</a></li><li class="chapter-item "><a href="../error/multiple_error_types/boxing_errors.html"><strong aria-hidden="true">18.4.3.</strong> Boxing errors</a></li><li class="chapter-item "><a href="../error/multiple_error_types/reenter_question_mark.html"><strong aria-hidden="true">18.4.4.</strong> Other uses of ?</a></li><li class="chapter-item "><a href="../error/multiple_error_types/wrap_error.html"><strong aria-hidden="true">18.4.5.</strong> Wrapping errors</a></li></ol></li><li class="chapter-item 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<h1 class="menu-title">Rust By Example</h1>
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<h1 id="vectors"><a class="header" href="#vectors">Vectors</a></h1>
<p>Vectors are re-sizable arrays. Like slices, their size is not known at compile
time, but they can grow or shrink at any time. A vector is represented using
3 parameters: </p>
<ul>
<li>pointer to the data</li>
<li>length</li>
<li>capacity </li>
</ul>
<p>The capacity indicates how much memory is reserved for the vector. The vector
can grow as long as the length is smaller than the capacity. When this threshold
needs to be surpassed, the vector is reallocated with a larger capacity.</p>
<pre><pre class="playground"><code class="language-rust editable ignore mdbook-runnable">fn main() {
// Iterators can be collected into vectors
let collected_iterator: Vec&lt;i32&gt; = (0..10).collect();
println!(&quot;Collected (0..10) into: {:?}&quot;, collected_iterator);
// The `vec!` macro can be used to initialize a vector
let mut xs = vec![1i32, 2, 3];
println!(&quot;Initial vector: {:?}&quot;, xs);
// Insert new element at the end of the vector
println!(&quot;Push 4 into the vector&quot;);
xs.push(4);
println!(&quot;Vector: {:?}&quot;, xs);
// Error! Immutable vectors can't grow
collected_iterator.push(0);
// FIXME ^ Comment out this line
// The `len` method yields the number of elements currently stored in a vector
println!(&quot;Vector length: {}&quot;, xs.len());
// Indexing is done using the square brackets (indexing starts at 0)
println!(&quot;Second element: {}&quot;, xs[1]);
// `pop` removes the last element from the vector and returns it
println!(&quot;Pop last element: {:?}&quot;, xs.pop());
// Out of bounds indexing yields a panic
println!(&quot;Fourth element: {}&quot;, xs[3]);
// FIXME ^ Comment out this line
// `Vector`s can be easily iterated over
println!(&quot;Contents of xs:&quot;);
for x in xs.iter() {
println!(&quot;&gt; {}&quot;, x);
}
// A `Vector` can also be iterated over while the iteration
// count is enumerated in a separate variable (`i`)
for (i, x) in xs.iter().enumerate() {
println!(&quot;In position {} we have value {}&quot;, i, x);
}
// Thanks to `iter_mut`, mutable `Vector`s can also be iterated
// over in a way that allows modifying each value
for x in xs.iter_mut() {
*x *= 3;
}
println!(&quot;Updated vector: {:?}&quot;, xs);
}
</code></pre></pre>
<p>More <code>Vec</code> methods can be found under the
<a href="https://doc.rust-lang.org/std/vec/">std::vec</a> module</p>
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