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<p class='location'>Trait Cast</p><div class="block items"><ul><li><a href="#provided-methods">Provided Methods</a></li><li><a href="#implementors">Implementors</a></li></ul></div><p class='location'><a href='../index.html'>glib</a>::<wbr><a href='index.html'>object</a></p><script>window.sidebarCurrent = {name: 'Cast', ty: 'trait', relpath: ''};</script><script defer src="sidebar-items.js"></script>
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<h1 class='fqn'><span class='in-band'>Trait <a href='../index.html'>glib</a>::<wbr><a href='index.html'>object</a>::<wbr><a class="trait" href=''>Cast</a></span><span class='out-of-band'><span id='render-detail'>
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</span><a class='srclink' href='../../src/glib/object.rs.html#23-61' title='goto source code'>[src]</a></span></h1>
<pre class='rust trait'>pub trait Cast: <a class="trait" href="../../glib/object/trait.IsA.html" title="trait glib::object::IsA">IsA</a><<a class="struct" href="../../glib/object/struct.Object.html" title="struct glib::object::Object">Object</a>> {
fn <a href='#method.upcast' class='fnname'>upcast</a><T>(self) -> T<br> <span class="where">where<br> T: <a class="trait" href="../../glib/types/trait.StaticType.html" title="trait glib::types::StaticType">StaticType</a> + <a class="trait" href="../../glib/wrapper/trait.UnsafeFrom.html" title="trait glib::wrapper::UnsafeFrom">UnsafeFrom</a><ObjectRef> + <a class="trait" href="../../glib/wrapper/trait.Wrapper.html" title="trait glib::wrapper::Wrapper">Wrapper</a>,<br> Self: <a class="trait" href="../../glib/object/trait.IsA.html" title="trait glib::object::IsA">IsA</a><T></span>,
{ ... }
fn <a href='#method.downcast' class='fnname'>downcast</a><T>(self) -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a><T, Self><br> <span class="where">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a> + <a class="trait" href="../../glib/object/trait.Downcast.html" title="trait glib::object::Downcast">Downcast</a><T></span>,
{ ... }
fn <a href='#method.is' class='fnname'>is</a><T>(&self) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a><br> <span class="where">where<br> Self: <a class="trait" href="../../glib/object/trait.Downcast.html" title="trait glib::object::Downcast">Downcast</a><T></span>,
{ ... }
}</pre><div class='docblock'><p>Upcasting and downcasting support.</p>
<p>Provides conversions up and down the class hierarchy tree.</p>
</div>
<h2 id='provided-methods'>Provided Methods</h2>
<div class='methods'>
<h3 id='method.upcast' class='method'><span id='upcast.v' class='invisible'><code>fn <a href='#method.upcast' class='fnname'>upcast</a><T>(self) -> T <span class="where fmt-newline">where<br> T: <a class="trait" href="../../glib/types/trait.StaticType.html" title="trait glib::types::StaticType">StaticType</a> + <a class="trait" href="../../glib/wrapper/trait.UnsafeFrom.html" title="trait glib::wrapper::UnsafeFrom">UnsafeFrom</a><ObjectRef> + <a class="trait" href="../../glib/wrapper/trait.Wrapper.html" title="trait glib::wrapper::Wrapper">Wrapper</a>,<br> Self: <a class="trait" href="../../glib/object/trait.IsA.html" title="trait glib::object::IsA">IsA</a><T>, </span></code></span></h3><div class='docblock'><p>Upcasts an object to a superclass or interface <code>T</code>.</p>
<h1 id='example' class='section-header'><a href='#example'>Example</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">button</span> <span class="op">=</span> <span class="ident">gtk</span>::<span class="ident">Button</span>::<span class="ident">new</span>();
<span class="kw">let</span> <span class="ident">widget</span> <span class="op">=</span> <span class="ident">button</span>.<span class="ident">upcast</span>::<span class="op"><</span><span class="ident">gtk</span>::<span class="ident">Widget</span><span class="op">></span>();</pre>
</div><h3 id='method.downcast' class='method'><span id='downcast.v' class='invisible'><code>fn <a href='#method.downcast' class='fnname'>downcast</a><T>(self) -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a><T, Self> <span class="where fmt-newline">where<br> Self: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a> + <a class="trait" href="../../glib/object/trait.Downcast.html" title="trait glib::object::Downcast">Downcast</a><T>, </span></code></span></h3><div class='docblock'><p>Tries to downcast to a subclass or interface implementor <code>T</code>.</p>
<p>Returns <code>Ok(T)</code> if the object is an instance of <code>T</code> and <code>Err(self)</code>
otherwise.</p>
<h1 id='example-1' class='section-header'><a href='#example-1'>Example</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">button</span> <span class="op">=</span> <span class="ident">gtk</span>::<span class="ident">Button</span>::<span class="ident">new</span>();
<span class="kw">let</span> <span class="ident">widget</span> <span class="op">=</span> <span class="ident">button</span>.<span class="ident">upcast</span>::<span class="op"><</span><span class="ident">gtk</span>::<span class="ident">Widget</span><span class="op">></span>();
<span class="macro">assert</span><span class="macro">!</span>(<span class="ident">widget</span>.<span class="ident">downcast</span>::<span class="op"><</span><span class="ident">gtk</span>::<span class="ident">Button</span><span class="op">></span>().<span class="ident">is_ok</span>());</pre>
</div><h3 id='method.is' class='method'><span id='is.v' class='invisible'><code>fn <a href='#method.is' class='fnname'>is</a><T>(&self) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a> <span class="where fmt-newline">where<br> Self: <a class="trait" href="../../glib/object/trait.Downcast.html" title="trait glib::object::Downcast">Downcast</a><T>, </span></code></span></h3><div class='docblock'><p>Returns <code>true</code> if the object is an instance of (can be downcast to) <code>T</code>.</p>
</div></div>
<h2 id='implementors'>Implementors</h2>
<ul class='item-list' id='implementors-list'>
<li><code>impl<T: <a class="trait" href="../../glib/object/trait.IsA.html" title="trait glib::object::IsA">IsA</a><<a class="struct" href="../../glib/object/struct.Object.html" title="struct glib::object::Object">Object</a>>> Cast for T</code></li>
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