flashblog/ruby.html at master · thlmenezes/flashblog · GitHub

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  <title>ruby</title>
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</head>
<body>
<section id="ruby" class="level1">
<h1><img src="https://cdn.emojidex.com/emoji/px64/Ruby.png?1465787635" /> Ruby</h1>
</section>
<section id="fontes" class="level1">
<h1><a href="https://www.ruby-lang.org/pt/">🍝</a> Fontes</h1>
<blockquote>
<p>“Já leu a documentação <a href="https://docs.ruby-lang.org/en/"><img src="https://cdn.emojidex.com/emoji/px32/Ruby.png?1465787635" /></a>?”<br/> Fábio Akita</p>
</blockquote>
</section>
<section id="matz" class="level1">
<h1>👺 Matz</h1>
<p><img src="https://upload.wikimedia.org/wikipedia/commons/7/76/Yukihiro_Matsumoto.JPG" /></p>
</section>
<section id="tudo-que-há-de-bom" class="level1">
<h1>🍲 “… tudo que há de bom”</h1>
<blockquote>
<p>“A liberdade do LISP com a expressividade do SmallTalk”<br/> <a href="https://youtu.be/oEorhw5r2Do?t=1906">Fabio Akita</a></p>
</blockquote>
</section>
<section id="pilares" class="level1">
<h1>🏛️ Pilares</h1>
<ul>
<li>😘 Multiparadigma</li>
<li>🤩 Interpretada</li>
<li>🎩 Sintaxe elegante
<ul>
<li>💡 <em>Convention Over Configuration</em></li>
</ul></li>
</ul>
</section>
<section id="gerenciadores-de-versão" class="level1">
<h1>🕴️ Gerenciadores de versão</h1>
<ul>
<li><a href="http://rvm.io">rvm</a> - Ruby Version Manager</li>
<li><a href="https://github.com/asdf-vm/asdf">asdf</a></li>
</ul>
</section>
<section id="bread-n-butter" class="level1">
<h1>🍞 Bread ’n Butter</h1>
<div class="sourceCode" id="cb1"><pre class="sourceCode ruby"><code class="sourceCode ruby"><span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="fu">puts</span> <span class="dv">4</span> <span class="kw">**</span> <span class="dv">10</span> <span class="co"># exponenciação</span></span>
<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a>var <span class="kw">=</span> <span class="fu">gets</span><span class="at">.chomp</span></span>
<span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="co">=begin</span></span>
<span id="cb1-4"><a href="#cb1-4" aria-hidden="true" tabindex="-1"></a><span class="co">! not, &amp;&amp; and, || or</span></span>
<span id="cb1-5"><a href="#cb1-5" aria-hidden="true" tabindex="-1"></a><span class="co">=end</span></span></code></pre></div>
<p><a href="https://docs.ruby-lang.org/en/2.6.0/String.html#method-i-chomp">chomp</a>, <a href="https://www.tutorialspoint.com/ruby/ruby_operators.htm">operadores</a></p>
</section>
<section id="methods" class="level1">
<h1>🛠 Methods?</h1>
<div class="sourceCode" id="cb2"><pre class="sourceCode ruby"><code class="sourceCode ruby"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="dv">3</span><span class="at">.class</span></span>
<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="dv">4</span><span class="at">.methods</span></span>
<span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="co"># Porque as `?` e `!`?</span></span>
<span id="cb2-4"><a href="#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="co"># =&gt; Convenção</span></span></code></pre></div>
</section>
<section id="strings" class="level1">
<h1>🧵 Strings</h1>
<div class="sourceCode" id="cb3"><pre class="sourceCode ruby"><code class="sourceCode ruby"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="dt">Thales</span> <span class="kw">=</span> <span class="st">&quot;oito&quot;</span></span>
<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="va">$nome</span> <span class="kw">=</span> <span class="wa">:Thales</span> <span class="co"># variável global</span></span>
<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a><span class="fu">puts</span> <span class="st">&quot;</span><span class="sc">#{</span><span class="va">$nome</span><span class="sc">}</span><span class="st">&quot;</span> <span class="co"># interpolação</span></span></code></pre></div>
</section>
<section id="símbolos" class="level1">
<h1><a href="https://docs.ruby-lang.org/en/2.7.0/Symbol.html">🔣</a> :Símbolos</h1>
<ul>
<li>Objeto imutável, nunca desalocado</li>
<li>Economizam memória</li>
<li><code>Symbol != object_id</code></li>
</ul>
</section>
<section id="na_prática" class="level1">
<h1>🔣 :na_prática</h1>
<ul>
<li>Usamos aos montes no Rails <br/>Perfomance executando Hashes</li>
<li>São identificadores, <a href="https://stackoverflow.com/questions/16621073/when-to-use-symbols-instead-of-strings-in-ruby#answers">Leia mais</a></li>
</ul>
</section>
<section id="bloco" class="level1">
<h1>🧱 Bloco</h1>
<div class="sourceCode" id="cb4"><pre class="sourceCode ruby"><code class="sourceCode ruby"><span id="cb4-1"><a href="#cb4-1" aria-hidden="true" tabindex="-1"></a><span class="kw">{</span> código cercado por chaves <span class="kw">}</span></span>
<span id="cb4-2"><a href="#cb4-2" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span> <span class="fu">puts</span> <span class="st">&quot;Também é bloco&quot;</span> <span class="cf">end</span></span>
<span id="cb4-3"><a href="#cb4-3" aria-hidden="true" tabindex="-1"></a><span class="co"># bloco pode receber argumentos</span></span>
<span id="cb4-4"><a href="#cb4-4" aria-hidden="true" tabindex="-1"></a><span class="dv">5</span><span class="at">.times</span> <span class="kw">{</span> <span class="kw">|</span>vez<span class="kw">|</span> <span class="fu">puts</span> vez <span class="kw">}</span></span></code></pre></div>
</section>
<section id="condicionais" class="level1">
<h1>🚦 Condicionais</h1>
<div class="sourceCode" id="cb5"><pre class="sourceCode ruby"><code class="sourceCode ruby"><span id="cb5-1"><a href="#cb5-1" aria-hidden="true" tabindex="-1"></a><span class="co"># Condicionais antes ou depois?</span></span>
<span id="cb5-2"><a href="#cb5-2" aria-hidden="true" tabindex="-1"></a><span class="fu">puts</span> <span class="st">&quot;É verdade que: 1 é menor que 2?&quot;</span> <span class="cf">if</span> <span class="dv">1</span> <span class="kw">&lt;</span> <span class="dv">2</span></span>
<span id="cb5-3"><a href="#cb5-3" aria-hidden="true" tabindex="-1"></a><span class="co"># Operador Ternário</span></span>
<span id="cb5-4"><a href="#cb5-4" aria-hidden="true" tabindex="-1"></a><span class="fu">puts</span> a <span class="kw">&gt;</span> <span class="dv">2</span> ? <span class="st">&quot;sim&quot;</span> : <span class="st">&quot;não é&quot;</span></span></code></pre></div>
</section>
<section id="expressões-de-controle" class="level1">
<h1>🎮 Expressões de controle</h1>
<ul>
<li>elsif <del>else if, elif</del></li>
<li>unless <del>if not</del></li>
<li><del>switch</del> case</li>
<li>until</li>
<li><a href="https://ruby-doc.org/core-2.7.1/doc/syntax/control_expressions_rdoc.html">Leia mais</a></li>
</ul>
</section>
<section id="arrays" class="level1">
<h1>🍱 Arrays</h1>
<div class="sourceCode" id="cb6"><pre class="sourceCode ruby"><code class="sourceCode ruby"><span id="cb6-1"><a href="#cb6-1" aria-hidden="true" tabindex="-1"></a>array <span class="kw">=</span> <span class="kw">[</span><span class="dv">1</span>,<span class="fl">1.0</span>,<span class="st">&quot;vinte&quot;</span><span class="kw">]</span></span>
<span id="cb6-2"><a href="#cb6-2" aria-hidden="true" tabindex="-1"></a>array <span class="kw">&lt;&lt;</span> <span class="st">&quot;Fagner&quot;</span></span>
<span id="cb6-3"><a href="#cb6-3" aria-hidden="true" tabindex="-1"></a><span class="co"># =&gt; [1, 1.0, &quot;vinte&quot;, &quot;Fagner&quot;]</span></span></code></pre></div>
</section>
<section id="acesso" class="level1">
<h1>♿ Acesso</h1>
<div class="sourceCode" id="cb7"><pre class="sourceCode ruby"><code class="sourceCode ruby"><span id="cb7-1"><a href="#cb7-1" aria-hidden="true" tabindex="-1"></a>array<span class="at">.at</span>(<span class="dv">20</span>)</span>
<span id="cb7-2"><a href="#cb7-2" aria-hidden="true" tabindex="-1"></a><span class="co"># =&gt; nil</span></span>
<span id="cb7-3"><a href="#cb7-3" aria-hidden="true" tabindex="-1"></a>array<span class="at">.fetch</span>(<span class="dv">20</span>)</span>
<span id="cb7-4"><a href="#cb7-4" aria-hidden="true" tabindex="-1"></a><span class="co"># =&gt; IndexError</span></span>
<span id="cb7-5"><a href="#cb7-5" aria-hidden="true" tabindex="-1"></a>array<span class="at">.fetch</span>(<span class="dv">20</span>,<span class="st">&quot;oopsie&quot;</span>)</span>
<span id="cb7-6"><a href="#cb7-6" aria-hidden="true" tabindex="-1"></a><span class="co"># =&gt; &quot;oopsie&quot;</span></span></code></pre></div>
</section>
<section id="for" class="level1">
<h1>🍴 <code>for</code></h1>
<ul>
<li>🙄 TL;DR Você não precisa dele</li>
<li><a href="https://github.com/rubocop-hq/ruby-style-guide#no-for-loops">Leia mais</a></li>
</ul>
</section>
<section id="iterando" class="level1">
<h1>🦼 Iterando</h1>
<div class="sourceCode" id="cb8"><pre class="sourceCode ruby"><code class="sourceCode ruby"><span id="cb8-1"><a href="#cb8-1" aria-hidden="true" tabindex="-1"></a>livros<span class="at">.each</span> <span class="kw">{</span> <span class="kw">|</span>livro<span class="kw">|</span></span>
<span id="cb8-2"><a href="#cb8-2" aria-hidden="true" tabindex="-1"></a>    <span class="fu">puts</span> livro</span>
<span id="cb8-3"><a href="#cb8-3" aria-hidden="true" tabindex="-1"></a><span class="kw">}</span></span>
<span id="cb8-4"><a href="#cb8-4" aria-hidden="true" tabindex="-1"></a>livros<span class="at">.each</span> <span class="cf">do</span> <span class="kw">|</span>livro<span class="kw">|</span></span>
<span id="cb8-5"><a href="#cb8-5" aria-hidden="true" tabindex="-1"></a>    <span class="fu">puts</span> livro</span>
<span id="cb8-6"><a href="#cb8-6" aria-hidden="true" tabindex="-1"></a><span class="cf">end</span></span>
<span id="cb8-7"><a href="#cb8-7" aria-hidden="true" tabindex="-1"></a>livros<span class="at">.each</span> <span class="cf">do</span> <span class="kw">|</span>l<span class="kw">|</span> <span class="fu">puts</span> l <span class="cf">end</span></span></code></pre></div>
</section>
<section id="encadeamento" class="level1">
<h1>🔗 Encadeamento</h1>
<div class="sourceCode" id="cb9"><pre class="sourceCode ruby"><code class="sourceCode ruby"><span id="cb9-1"><a href="#cb9-1" aria-hidden="true" tabindex="-1"></a>poema<span class="at">.lines.reverse.join</span></span></code></pre></div>
</section>
<section id="reflexão" class="level1">
<h1>🤔 Reflexão</h1>
<blockquote>
<p>“It’s not good enough just to get your code to work, your code has to be something that you love to work in”<br/><a href="https://youtu.be/oEorhw5r2Do?t=4389">Robert Martin</a></p>
</blockquote>
</section>
<section id="exercite-se" class="level1">
<h1>🦾 Exercite-se</h1>
<p>Tutorial interativo <a href="https://try.ruby-lang.org">Try Ruby</a><br/>Complete <a href="http://www.rubykoans.com">The Koans</a></p>
</section>
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