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class="prism-code language-go codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token keyword" style="font-style:italic">type</span><span class="token plain"> instrumentSounds </span><span class="token keyword" style="font-style:italic">interface</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(199, 146, 234)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> </span><span class="token function" style="color:rgb(130, 170, 255)">makeBand</span><span class="token punctuation" style="color:rgb(199, 146, 234)">(</span><span class="token punctuation" style="color:rgb(199, 146, 234)">)</span><span class="token plain"> </span><span class="token builtin" style="color:rgb(130, 170, 255)">string</span><span class="token plain"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"></span><span class="token punctuation" style="color:rgb(199, 146, 234)">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>So this is our instrumentSounds interface which calls a function makeBand. </p><div style="padding-bottom:1rem;width:100%"><button class="button button--primary">open playground</button> <a href="https://goplay.tools/snippet/p-Ut2K0Fa9f" target="_blank" rel="noopener noreferrer">go to <!-- -->https://goplay.tools/snippet/p-Ut2K0Fa9f</a></div><pre class="prism-code language-go" style="background-color:#2a2734;color:#9a86fd">... loading sources<div class="token-line" style="color:#9a86fd"><span class="token plain" style="display:inline-block">
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</span></div></pre><div style="display:none"><div><button class="button button--lg button--secondary">load external go playground, with all it´s potentially evil cookies coming from https://goplay.tools</button></div></div><h2 class="anchor anchorWithStickyNavbar_LWe7" id="the-empty-interface">The Empty Interface<a href="#the-empty-interface" class="hash-link" aria-label="Direct link to The Empty Interface" title="Direct link to The Empty Interface"></a></h2><p>An empty interface can hold values that satisfy any type. It's commonly used in code when the values types are unknown.</p><div class="language-go codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-go codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"></span><span class="token keyword" style="font-style:italic">func</span><span class="token plain"> </span><span class="token function" style="color:rgb(130, 170, 255)">main</span><span class="token punctuation" style="color:rgb(199, 146, 234)">(</span><span class="token punctuation" style="color:rgb(199, 146, 234)">)</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(199, 146, 234)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> </span><span class="token keyword" style="font-style:italic">var</span><span class="token plain"> myInterface </span><span class="token keyword" style="font-style:italic">interface</span><span class="token punctuation" style="color:rgb(199, 146, 234)">{</span><span class="token punctuation" style="color:rgb(199, 146, 234)">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> myInterface </span><span class="token operator" style="color:rgb(137, 221, 255)">=</span><span class="token plain"> </span><span class="token number" style="color:rgb(247, 140, 108)">300</span><span class="token plain"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> fmt</span><span class="token punctuation" style="color:rgb(199, 146, 234)">.</span><span class="token function" style="color:rgb(130, 170, 255)">Println</span><span class="token punctuation" style="color:rgb(199, 146, 234)">(</span><span class="token plain">myInterface</span><span class="token punctuation" style="color:rgb(199, 146, 234)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> myInterface </span><span class="token operator" style="color:rgb(137, 221, 255)">=</span><span class="token plain"> </span><span class="token string" style="color:rgb(195, 232, 141)">"Hello world"</span><span class="token plain"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"> fmt</span><span class="token punctuation" style="color:rgb(199, 146, 234)">.</span><span class="token function" style="color:rgb(130, 170, 255)">Println</span><span class="token punctuation" style="color:rgb(199, 146, 234)">(</span><span class="token plain">myInterface</span><span class="token punctuation" style="color:rgb(199, 146, 234)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain"></span><span class="token punctuation" style="color:rgb(199, 146, 234)">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>Even though the type is changed this program will still work fine because myInterface is an empty interface so it could be of any type.
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