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30secondsofcode
2019-06-05 07:47:17 +00:00
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15
README.md
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@ -8,8 +8,6 @@
> Curated collection of useful JavaScript snippets that you can understand in 30 seconds or less.
[![Sponsored by DigitalOcean](/sponsored_by_DigitalOcean.png)](https://www.digitalocean.com)
* Use <kbd>Ctrl</kbd> + <kbd>F</kbd> or <kbd>command</kbd> + <kbd>F</kbd> to search for a snippet.
* Contributions welcome, please read the [contribution guide](CONTRIBUTING.md).
* Snippets are written in ES6, use the [Babel transpiler](https://babeljs.io/) to ensure backwards-compatibility.
@ -680,7 +678,7 @@ const sum = pipeAsyncFunctions(
x => x + 3,
async x => (await x) + 4
);
(async () => {
(async() => {
console.log(await sum(5)); // 15 (after one second)
})();
```
@ -2330,9 +2328,9 @@ The `func` is invoked with three arguments (`value, index, array`).
const remove = (arr, func) =>
Array.isArray(arr)
? arr.filter(func).reduce((acc, val) => {
arr.splice(arr.indexOf(val), 1);
return acc.concat(val);
}, [])
arr.splice(arr.indexOf(val), 1);
return acc.concat(val);
}, [])
: [];
```
@ -4745,6 +4743,7 @@ const checkProp = (predicate, prop) => obj => !!predicate(obj[prop]);
const lengthIs4 = checkProp(l => l === 4, 'length');
lengthIs4([]); // false
lengthIs4([1,2,3,4]); // true
@ -5621,8 +5620,8 @@ Throws an exception if `n` is a negative number.
const factorial = n =>
n < 0
? (() => {
throw new TypeError('Negative numbers are not allowed!');
})()
throw new TypeError('Negative numbers are not allowed!');
})()
: n <= 1
? 1
: n * factorial(n - 1);

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docs/about.html
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@ -582,8 +582,7 @@
<p style="display: inline-block;"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a>
license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a
href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a>
license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align: sub; padding-right: 2px; padding-left: 2px;"
width="20px" height="20px" alt="DigitalOcean"><a href="https://www.digitalocean.com"><span style="color:#0080ff">DigitalOcean</span></a></p>
license.</p>
<br />
<p style="display: inline-block;"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a
href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p>

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@ -133,7 +133,7 @@ Object<span class="token punctuation">.</span><span class="token function">assig
x <span class="token operator">=></span> x <span class="token operator">+</span> <span class="token number">3</span><span class="token punctuation">,</span>
<span class="token keyword">async</span> x <span class="token operator">=></span> <span class="token punctuation">(</span><span class="token keyword">await</span> x<span class="token punctuation">)</span> <span class="token operator">+</span> <span class="token number">4</span>
<span class="token punctuation">);
(</span><span class="token keyword">async</span> <span class="token punctuation">()</span> <span class="token operator">=></span> <span class="token punctuation">{</span>
(</span><span class="token keyword">async</span><span class="token punctuation">()</span> <span class="token operator">=></span> <span class="token punctuation">{</span>
console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span><span class="token keyword">await</span> <span class="token function">sum</span><span class="token punctuation">(</span><span class="token number">5</span><span class="token punctuation">));</span> <span class="token comment">// 15 (after one second)</span>
<span class="token punctuation">})();</span>
</pre></div><div class="card code-card"><div class="section card-content"><h4><a href="https://frontendmasters.com/courses/es6-right-parts/" target="_blank" rel="noopener noreferrer">Recommended Resource - ES6: The Right Parts</a></h4><p>Learn new ES6 JavaScript language features like arrow function, destructuring, generators & more to write cleaner and more productive, readable programs.</p></div></div><div class="card code-card"><div class="corner intermediate" aria-label="intermediate" title="intermediate"></div><div class="section card-content"><h4 id="pipefunctions">pipeFunctions</h4><p>Performs left-to-right function composition.</p><p>Use <code>Array.prototype.reduce()</code> with the spread operator (<code>...</code>) to perform left-to-right function composition. The first (leftmost) function can accept one or more arguments; the remaining functions must be unary.</p></div><div class="copy-button-container"><button class="copy-button" aria-label="Copy to clipboard"></button></div><pre class="section card-code language-js"><span class="token keyword">const</span> <span class="token function-variable function">pipeFunctions</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token operator">...</span>fns<span class="token punctuation">)</span> <span class="token operator">=></span> fns<span class="token punctuation">.</span><span class="token function">reduce</span><span class="token punctuation">((</span>f<span class="token punctuation">,</span> g<span class="token punctuation">)</span> <span class="token operator">=></span> <span class="token punctuation">(</span><span class="token operator">...</span>args<span class="token punctuation">)</span> <span class="token operator">=></span> <span class="token function">g</span><span class="token punctuation">(</span><span class="token function">f</span><span class="token punctuation">(</span><span class="token operator">...</span>args<span class="token punctuation">)));</span>
@ -160,4 +160,4 @@ Object<span class="token punctuation">.</span><span class="token function">assig
<span class="token function">arrayMax</span><span class="token punctuation">([</span><span class="token number">1</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">,</span> <span class="token number">3</span><span class="token punctuation">]);</span> <span class="token comment">// 3</span>
</pre></div><div class="card code-card"><div class="corner intermediate" aria-label="intermediate" title="intermediate"></div><div class="section card-content"><h4 id="unary">unary</h4><p>Creates a function that accepts up to one argument, ignoring any additional arguments.</p><p>Call the provided function, <code>fn</code>, with just the first argument given.</p></div><div class="copy-button-container"><button class="copy-button" aria-label="Copy to clipboard"></button></div><pre class="section card-code language-js"><span class="token keyword">const</span> <span class="token function-variable function">unary</span> <span class="token operator">=</span> fn <span class="token operator">=></span> val <span class="token operator">=></span> <span class="token function">fn</span><span class="token punctuation">(</span>val<span class="token punctuation">);</span>
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token punctuation">[</span><span class="token string">'6'</span><span class="token punctuation">,</span> <span class="token string">'8'</span><span class="token punctuation">,</span> <span class="token string">'10'</span><span class="token punctuation">].</span><span class="token function">map</span><span class="token punctuation">(</span><span class="token function">unary</span><span class="token punctuation">(</span>parseInt<span class="token punctuation">));</span> <span class="token comment">// [6, 8, 10]</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

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@ -289,4 +289,4 @@
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token function">speechSynthesis</span><span class="token punctuation">(</span><span class="token string">'Hello, World'</span><span class="token punctuation">);</span> <span class="token comment">// // plays the message</span>
</pre></div><div class="card code-card"><div class="section card-content"><h4 id="squaresum.md">squareSum</h4><p>Squares each number in an array and then sums the results together.</p><p>Use <code>Array.prototype.reduce()</code> in combination with <code>Math.pow()</code> to iterate over numbers and sum their squares into an accumulator.</p></div><div class="copy-button-container"><button class="copy-button" aria-label="Copy to clipboard"></button></div><pre class="section card-code language-js"><span class="token keyword">const</span> <span class="token function-variable function">squareSum</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token operator">...</span>args<span class="token punctuation">)</span> <span class="token operator">=></span> args<span class="token punctuation">.</span><span class="token function">reduce</span><span class="token punctuation">((</span>squareSum<span class="token punctuation">,</span> number<span class="token punctuation">)</span> <span class="token operator">=></span> squareSum <span class="token operator">+</span> Math<span class="token punctuation">.</span><span class="token function">pow</span><span class="token punctuation">(</span>number<span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">),</span> <span class="token number">0</span><span class="token punctuation">);</span>
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token function">squareSum</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">);</span> <span class="token comment">// 9</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px" alt="DigitalOcean"><a href="https://www.digitalocean.com"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

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@ -393,4 +393,4 @@ recorder<span class="token punctuation">.</span><span class="token function">sta
<span class="token punctuation">(</span>c <span class="token operator">^</span> <span class="token punctuation">(</span>crypto<span class="token punctuation">.</span><span class="token function">getRandomValues</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">Uint8Array</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">))[</span><span class="token number">0</span><span class="token punctuation">]</span> <span class="token operator">&amp;</span> <span class="token punctuation">(</span><span class="token number">15</span> <span class="token operator">>></span> <span class="token punctuation">(</span>c <span class="token operator">/</span> <span class="token number">4</span><span class="token punctuation">)))).</span><span class="token function">toString</span><span class="token punctuation">(</span><span class="token number">16</span><span class="token punctuation">)
);</span>
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token function">UUIDGeneratorBrowser</span><span class="token punctuation">();</span> <span class="token comment">// '7982fcfe-5721-4632-bede-6000885be57d'</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

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@ -157,4 +157,4 @@
<span class="token keyword">return</span> t<span class="token punctuation">.</span><span class="token function">toISOString</span><span class="token punctuation">().</span><span class="token function">split</span><span class="token punctuation">(</span><span class="token string">'T'</span><span class="token punctuation">)[</span><span class="token number">0</span><span class="token punctuation">];
};</span>
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token function">tomorrow</span><span class="token punctuation">();</span> <span class="token comment">// 2018-10-19 (if current date is 2018-10-18)</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

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@ -161,6 +161,7 @@ console<span class="token punctuation">.</span><span class="token function">log<
<span class="token keyword">const</span> lengthIs4 <span class="token operator">=</span> <span class="token function">checkProp</span><span class="token punctuation">(</span>l <span class="token operator">=></span> l <span class="token operator">===</span> <span class="token number">4</span><span class="token punctuation">,</span> <span class="token string">'length'</span><span class="token punctuation">);</span>
<span class="token function">lengthIs4</span><span class="token punctuation">([]);</span> <span class="token comment">// false</span>
<span class="token function">lengthIs4</span><span class="token punctuation">([</span><span class="token number">1</span><span class="token punctuation">,</span><span class="token number">2</span><span class="token punctuation">,</span><span class="token number">3</span><span class="token punctuation">,</span><span class="token number">4</span><span class="token punctuation">]);</span> <span class="token comment">// true</span>
@ -352,4 +353,4 @@ console<span class="token punctuation">.</span><span class="token function">log<
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token keyword">const</span> doubleEvenNumbers <span class="token operator">=</span> <span class="token function">when</span><span class="token punctuation">(</span>x <span class="token operator">=></span> x <span class="token operator">%</span> <span class="token number">2</span> <span class="token operator">===</span> <span class="token number">0</span><span class="token punctuation">,</span> x <span class="token operator">=></span> x <span class="token operator">*</span> <span class="token number">2</span><span class="token punctuation">);</span>
<span class="token function">doubleEvenNumbers</span><span class="token punctuation">(</span><span class="token number">2</span><span class="token punctuation">);</span> <span class="token comment">// 4</span>
<span class="token function">doubleEvenNumbers</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">);</span> <span class="token comment">// 1</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

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@ -152,8 +152,8 @@ own individual rating by supplying it as the third argument.
</pre></div><div class="card code-card"><div class="corner beginner" aria-label="beginner" title="beginner"></div><div class="section card-content"><h4 id="factorial">factorial</h4><p>Calculates the factorial of a number.</p><p>Use recursion. If <code>n</code> is less than or equal to <code>1</code>, return <code>1</code>. Otherwise, return the product of <code>n</code> and the factorial of <code>n - 1</code>. Throws an exception if <code>n</code> is a negative number.</p></div><div class="copy-button-container"><button class="copy-button" aria-label="Copy to clipboard"></button></div><pre class="section card-code language-js"><span class="token keyword">const</span> <span class="token function-variable function">factorial</span> <span class="token operator">=</span> n <span class="token operator">=></span>
n <span class="token operator">&lt;</span> <span class="token number">0</span>
<span class="token operator">?</span> <span class="token punctuation">(()</span> <span class="token operator">=></span> <span class="token punctuation">{</span>
<span class="token keyword">throw new</span> <span class="token class-name">TypeError</span><span class="token punctuation">(</span><span class="token string">'Negative numbers are not allowed!'</span><span class="token punctuation">);
})()
<span class="token keyword">throw new</span> <span class="token class-name">TypeError</span><span class="token punctuation">(</span><span class="token string">'Negative numbers are not allowed!'</span><span class="token punctuation">);
})()
:</span> n <span class="token operator">&lt;=</span> <span class="token number">1</span>
<span class="token operator">?</span> <span class="token number">1</span>
<span class="token punctuation">:</span> n <span class="token operator">*</span> <span class="token function">factorial</span><span class="token punctuation">(</span>n <span class="token operator">-</span> <span class="token number">1</span><span class="token punctuation">);</span>
@ -308,4 +308,4 @@ own individual rating by supplying it as the third argument.
<span class="token keyword">return</span> Math<span class="token punctuation">.</span><span class="token function">sqrt</span><span class="token punctuation">(</span>sum<span class="token punctuation">);
};</span>
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token function">vectorDistance</span><span class="token punctuation">(</span><span class="token number">10</span><span class="token punctuation">,</span> <span class="token number">0</span><span class="token punctuation">,</span> <span class="token number">5</span><span class="token punctuation">,</span> <span class="token number">20</span><span class="token punctuation">,</span> <span class="token number">0</span><span class="token punctuation">,</span> <span class="token number">10</span><span class="token punctuation">);</span> <span class="token comment">// 11.180339887498949</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

2
docs/node.html
View File

@ -200,4 +200,4 @@ console<span class="token punctuation">.</span><span class="token function">log<
<span class="token punctuation">(</span>c <span class="token operator">^</span> <span class="token punctuation">(</span>crypto<span class="token punctuation">.</span><span class="token function">randomBytes</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">)[</span><span class="token number">0</span><span class="token punctuation">]</span> <span class="token operator">&amp;</span> <span class="token punctuation">(</span><span class="token number">15</span> <span class="token operator">>></span> <span class="token punctuation">(</span>c <span class="token operator">/</span> <span class="token number">4</span><span class="token punctuation">)))).</span><span class="token function">toString</span><span class="token punctuation">(</span><span class="token number">16</span><span class="token punctuation">)
);</span>
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token function">UUIDGeneratorNode</span><span class="token punctuation">();</span> <span class="token comment">// '79c7c136-60ee-40a2-beb2-856f1feabefc'</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

2
docs/object.html
View File

@ -439,4 +439,4 @@ Foo<span class="token punctuation">.</span>prototype<span class="token punctuati
<span class="token keyword">return</span> acc<span class="token punctuation">;
}, {});</span>
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token function">unflattenObject</span><span class="token punctuation">({</span> <span class="token string">'a.b.c'</span><span class="token punctuation">:</span> <span class="token number">1</span><span class="token punctuation">,</span> d<span class="token punctuation">:</span> <span class="token number">1</span> <span class="token punctuation">});</span> <span class="token comment">// { a: { b: { c: 1 } }, d: 1 }</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

2
docs/string.html
View File

@ -309,4 +309,4 @@
</pre></div><div class="card code-card"><div class="corner intermediate" aria-label="intermediate" title="intermediate"></div><div class="section card-content"><h4 id="words">words</h4><p>Converts a given string into an array of words.</p><p>Use <code>String.prototype.split()</code> with a supplied pattern (defaults to non-alpha as a regexp) to convert to an array of strings. Use <code>Array.prototype.filter()</code> to remove any empty strings. Omit the second argument to use the default regexp.</p></div><div class="copy-button-container"><button class="copy-button" aria-label="Copy to clipboard"></button></div><pre class="section card-code language-js"><span class="token keyword">const</span> words <span class="token operator">=</span> <span class="token punctuation">(</span>str<span class="token punctuation">,</span> pattern <span class="token operator">=</span> <span class="token regex">/[^a-zA-Z-]+/</span><span class="token punctuation">)</span> <span class="token operator">=></span> str<span class="token punctuation">.</span><span class="token function">split</span><span class="token punctuation">(</span>pattern<span class="token punctuation">).</span><span class="token function">filter</span><span class="token punctuation">(</span>Boolean<span class="token punctuation">);</span>
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token function">words</span><span class="token punctuation">(</span><span class="token string">'I love javaScript!!'</span><span class="token punctuation">);</span> <span class="token comment">// ["I", "love", "javaScript"]</span>
<span class="token function">words</span><span class="token punctuation">(</span><span class="token string">'python, javaScript &amp; coffee'</span><span class="token punctuation">);</span> <span class="token comment">// ["python", "javaScript", "coffee"]</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

2
docs/type.html
View File

@ -188,4 +188,4 @@
</pre><label class="collapse">examples</label><pre class="section card-examples language-js"><span class="token function">isValidJSON</span><span class="token punctuation">(</span><span class="token string">'{"name":"Adam","age":20}'</span><span class="token punctuation">);</span> <span class="token comment">// true</span>
<span class="token function">isValidJSON</span><span class="token punctuation">(</span><span class="token string">'{"name":"Adam",age:"20"}'</span><span class="token punctuation">);</span> <span class="token comment">// false</span>
<span class="token function">isValidJSON</span><span class="token punctuation">(</span><span class="token keyword">null</span><span class="token punctuation">);</span> <span class="token comment">// true</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

2
docs/utility.html
View File

@ -286,4 +286,4 @@ Logs: {
<span class="token function">yesNo</span><span class="token punctuation">(</span><span class="token string">'yes'</span><span class="token punctuation">);</span> <span class="token comment">// true</span>
<span class="token function">yesNo</span><span class="token punctuation">(</span><span class="token string">'No'</span><span class="token punctuation">);</span> <span class="token comment">// false</span>
<span class="token function">yesNo</span><span class="token punctuation">(</span><span class="token string">'Foo'</span><span class="token punctuation">,</span> <span class="token boolean">true</span><span class="token punctuation">);</span> <span class="token comment">// true</span>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.<br>Sponsored by <img src="https://30secondsofcode.org/sponsors/DO_Logo_icon_blue.svg" style="vertical-align:sub;padding-right:2px;padding-left:2px" width="20px" height="20px"><a href="https://www.digitalocean.com" alt="DigitalOcean"><span style="color:#0080ff">DigitalOcean</span></a>.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>
</pre></div></main><footer class="col-full-width container"><div class="col-centered"><p style="display:inline-block"><strong>30 seconds of code</strong> is licensed under the <a href="https://github.com/30-seconds/30-seconds-of-code/blob/master/LICENSE">CC0-1.0</a> license.<br>Logos made by <a href="https://github.com/Chalarangelo">Angelos Chalaris</a> and ribbon made by <a href="https://github.com/tholman/github-corners">Tim Holman</a> are licensed under the <a href="https://opensource.org/licenses/MIT">MIT</a> license.</p><br/><p style="display:inline-block"><a href="./about">About</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./contributing">Contributing</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./archive">Archive</a>&nbsp;&nbsp;&nbsp;&nbsp;<a href="./glossary">Glossary</a></p></div></footer><a class="scroll-to-top" href="#top"></a></div></body></html>

1
snippets/checkProp.md
View File

@ -26,6 +26,7 @@ const checkProp = (predicate, prop) => obj => !!predicate(obj[prop]);
const lengthIs4 = checkProp(l => l === 4, 'length');
lengthIs4([]); // false
lengthIs4([1,2,3,4]); // true

4
snippets/factorial.md
View File

@ -11,8 +11,8 @@ Throws an exception if `n` is a negative number.
const factorial = n =>
n < 0
? (() => {
throw new TypeError('Negative numbers are not allowed!');
})()
throw new TypeError('Negative numbers are not allowed!');
})()
: n <= 1
? 1
: n * factorial(n - 1);

2
snippets/pipeAsyncFunctions.md
View File

@ -17,7 +17,7 @@ const sum = pipeAsyncFunctions(
x => x + 3,
async x => (await x) + 4
);
(async () => {
(async() => {
console.log(await sum(5)); // 15 (after one second)
})();
```

6
snippets/remove.md
View File

@ -9,9 +9,9 @@ The `func` is invoked with three arguments (`value, index, array`).
const remove = (arr, func) =>
Array.isArray(arr)
? arr.filter(func).reduce((acc, val) => {
arr.splice(arr.indexOf(val), 1);
return acc.concat(val);
}, [])
arr.splice(arr.indexOf(val), 1);
return acc.concat(val);
}, [])
: [];
```

10
test/_30s.js
View File

@ -347,8 +347,8 @@ const extendHex = shortHex =>
const factorial = n =>
n < 0
? (() => {
throw new TypeError('Negative numbers are not allowed!');
})()
throw new TypeError('Negative numbers are not allowed!');
})()
: n <= 1
? 1
: n * factorial(n - 1);
@ -1004,9 +1004,9 @@ const reject = (pred, array) => array.filter((...args) => !pred(...args));
const remove = (arr, func) =>
Array.isArray(arr)
? arr.filter(func).reduce((acc, val) => {
arr.splice(arr.indexOf(val), 1);
return acc.concat(val);
}, [])
arr.splice(arr.indexOf(val), 1);
return acc.concat(val);
}, [])
: [];
const removeNonASCII = str => str.replace(/[^\x20-\x7E]/g, '');
const renameKeys = (keysMap, obj) =>