<!DOCTYPE html><html><head><metacharset="utf-8"><metaname="viewport"content="width=device-width, initial-scale=1"><linkrel="stylesheet"href="index.css"><metaname="description"content="Introducing basic concepts."><!--<dde:mark type="component" name="metaTwitter" host="this"/>--><metaname="twitter:card"content="summary_large_image"><metaname="twitter:url"content="https://github.com/jaandrle/deka-dom-el"><metaname="twitter:title"content="deka-dom-el"><metaname="twitter:description"content="A low-code library that simplifies the creation of native DOM elements/components using small wrappers and tweaks."><metaname="twitter:creator"content="@jaandrle"><!--<dde:mark type="component" name="metaFacebook" host="this"/>--><metaname="og:url"content="https://github.com/jaandrle/deka-dom-el"><metaname="og:title"content="deka-dom-el"><metaname="og:description"content="A low-code library that simplifies the creation of native DOM elements/components using small wrappers and tweaks."><metaname="og:creator"content="@jaandrle"><title>`deka-dom-el` — Introduction/Guide</title><scriptsrc="https://flems.io/flems.html"type="text/javascript"charset="utf-8"></script></head><body><!--<dde:mark type="component" name="body" host="this"/>--><h1>`deka-dom-el` — Introduction/Guide</h1><p>The library tries to provide pure JavaScript tool(s) to create reactive interfaces. The main goals are:</p><ul><li>provide a small wrappers/utilities around the native JavaScript DOM</li><li>keep library size around 10kB at maximum (if possible)</li><li>zero dependencies (if possible)</li><li>prefer a declarative/functional approach</li><li>unopinionated (allow alternative methods)</li></ul><pclass="note">It is, in fact, an reimplementation of <ahref="https://github.com/jaandrle/dollar_dom_component"title="GitHub repository of library. Motto: Functional DOM components without JSX and virtual DOM.">jaandrle/dollar_dom_component</a>.</p><!--<dde:mark type="component" name="example" host="this"/>--><divid="code-hrmiy"class="example"><pre><codeclass="language-javascript">import { el, S } from "https://cdn.jsdelivr.net/gh/jaandrle/deka-dom-el/dist/esm-with-signals.js";
</code></pre></div><script>Flems(document.getElementById("code-hrmiy"),JSON.parse("{\"files\":[{\"name\":\".js\",\"content\":\"import { el, S } from \\\"https://cdn.jsdelivr.net/gh/jaandrle/deka-dom-el/dist/esm-with-signals.js\\\";\\nconst clicks= S(0);\\ndocument.body.append(\\n\\tel().append(\\n\\t\\tel(\\\"p\\\", S(()=>\\n\\t\\t\\t\\\"Hello World \\\"+\\\"🎉\\\".repeat(clicks())\\n\\t\\t)),\\n\\t\\tel(\\\"button\\\", {\\n\\t\\t\\ttype: \\\"button\\\",\\n\\t\\t\\tonclick: ()=> clicks(clicks()+1),\\n\\t\\t\\ttextContent: \\\"Fire\\\"\\n\\t\\t})\\n\\t)\\n);\\n\"}],\"toolbar\":false}"));</script><h2>Native JavaScript DOM elements creations</h2><p>Let’s go through all patterns we would like to use and what needs to be improved for better experience.</p><h3>Creating element(s) (with custom attributes)</h3><p>You can create a native DOM element by using the <ahref="https://developer.mozilla.org/en-US/docs/Web/API/Document/createElement"title="MDN documentation for document.createElement()"><code>document.createElement()</code></a>. It is also possible to provide a some attribute(s) declaratively using <code>Object.assign()</code>. More precisely, this way you can sets some <ahref="https://developer.mozilla.org/en-US/docs/Glossary/IDL"title="MDN page about Interface Description Language"><abbrtitle="Interface Description Language">IDL</abbr></a>.</p><!--<dde:mark type="component" name="example" host="this"/>--><divid="code-x0k3n"class="example"><pre><codeclass="language-javascript">document.body.append(
</code></pre></div><script>Flems(document.getElementById("code-x0k3n"),JSON.parse("{\"files\":[{\"name\":\".js\",\"content\":\"document.body.append(\\n\\tdocument.createElement(\\\"div\\\")\\n);\\nconsole.log(\\n\\t\\\"Emty div is generated inside <body>:\\\",\\n\\tdocument.body.innerHTML.includes(\\\"<div></div>\\\")\\n);\\n\\ndocument.body.append(\\n\\tObject.assign(\\n\\t\\tdocument.createElement(\\\"p\\\"),\\n\\t\\t{ textContent: \\\"Element’s text content.\\\", style: \\\"color: coral;\\\" }\\n\\t)\\n);\\n\"}],\"toolbar\":false}"));</script><p>To make this easier, you can use the <code>el</code> function. Internally in basic examples, it is wrapper around <code>assign(document.createElement(…), { … })</code>.</p><!--<dde:mark type="component" name="example" host="this"/>--><divid="code-tz88s"class="example"><pre><codeclass="language-javascript">import { el, assign } from "https://cdn.jsdelivr.net/gh/jaandrle/deka-dom-el/dist/esm-with-signals.js";
</code></pre></div><script>Flems(document.getElementById("code-tz88s"),JSON.parse("{\"files\":[{\"name\":\".js\",\"content\":\"import { el, assign } from \\\"https://cdn.jsdelivr.net/gh/jaandrle/deka-dom-el/dist/esm-with-signals.js\\\";\\nconst color= \\\"lightcoral\\\";\\ndocument.body.append(\\n\\tel(\\\"p\\\", { textContent: \\\"Hello (first time)\\\", style: { color } })\\n);\\ndocument.body.append(\\n\\tassign(\\n\\t\\tdocument.createElement(\\\"p\\\"),\\n\\t\\t{ textContent: \\\"Hello (second time)\\\", style: { color } }\\n\\t)\\n);\\n\"}],\"toolbar\":false}"));</script><p>The <code>assign</code> function provides improved behaviour of <code>Object.assign()</code>. You can declaratively sets any IDL and attribute of the given element. Function prefers IDL and fallback to the <code>element.setAttribute</code> if there is no writable property in the element prototype.</p><p>You can study all JavaScript elements interfaces to the corresponding HTML elements. All HTML elements inherits from <ahref="https://developer.mozilla.org/en-US/docs/Web/API/HTMLElement">HTMLElement</a>. To see all available IDLs for example for paragraphs, see <ahref="https://developer.mozilla.org/en-US/docs/Web/API/HTMLParagraphElement">HTMLParagraphElement</a>. Moreover, the <code>assign</code> provides a way to sets declaratively some convenient properties:</p><ul><li>It is possible to sets <code>data-*</code>/<code>aria-*</code> attributes using object notation.</li><li>In opposite, it is also possible to sets <code>data-*</code>/<code>aria-*</code> attribute using camelCase notation.</li><li>You can use string or object as a value for <code>style</code> property.</li><li><code>className</code> (IDL – preffered)/<code>class</code> are ways to add CSS class to the element. You can use string (similarly to <code>class="…"</code> syntax in HTML) or array of strings. This is handy to concat conditional classes.</li><li>Use <code>classList</code> to toggle specific classes. This will be handy later when the reactivity via signals is beeing introduced.</li><li>The <code>assign</code> also accepts the <code>undefined</code> as a value for any property to remove it from the element declaratively. Also for some IDL the corresponding attribute is removed as it can be confusing. <em>For example, natievly the element’s <code>id</code> is removed by setting the IDL to an empty string.</em></li></ul><p>For processing, the <code>assign</code> internally uses <code>assignAttribute</code> and <code>classListDeclarative</code>.</p><!--<dde:mark type="component" name="example" host="this"/>--><divid="code-8doer"class="example"><pre><codeclass="language-javascript">import { assignAttribute, classListDeclarative } from "https://cdn.jsdelivr.net/gh/jaandrle/deka-dom-el/dist/esm-with-signals.js";
</code></pre></div><script>Flems(document.getElementById("code-ya3r1"),JSON.parse("{\"files\":[{\"name\":\".js\",\"content\":\"import { el } from \\\"https://cdn.jsdelivr.net/gh/jaandrle/deka-dom-el/dist/esm-with-signals.js\\\";\\ndocument.head.append(\\n\\tel(\\\"style\\\").append(\\n\\t\\t\\\"tr, td{ border: 1px solid red; padding: 1em; }\\\",\\n\\t\\t\\\"table{ border-collapse: collapse; }\\\"\\n\\t)\\n);\\ndocument.body.append(\\n\\tel(\\\"p\\\", \\\"Example of acomplex template. Using for example nesting lists:\\\"),\\n\\tel(\\\"ul\\\").append(\\n\\t\\tel(\\\"li\\\", \\\"List item 1\\\"),\\n\\t\\tel(\\\"li\\\").append(\\n\\t\\t\\tel(\\\"ul\\\").append(\\n\\t\\t\\t\\tel(\\\"li\\\", \\\"Nested list item 1\\\"),\\n\\t\\t\\t)\\n\\t\\t)\\n\\t),\\n\\tel(\\\"table\\\").append(\\n\\t\\tel(\\\"tr\\\").append(\\n\\t\\t\\tel(\\\"td\\\", \\\"Row 1 – Col 1\\\"),\\n\\t\\t\\tel(\\\"td\\\", \\\"Row 1 – Col 2\\\")\\n\\t\\t)\\n\\t)\\n);\\n\"}],\"toolbar\":false}"));</script><h2>Creating advanced (reactive) templates and components</h2><h3>Basic components</h3><p>You can use functions for encapsulation (repeating) logic. The <code>el</code> accepts function as first argument. In that case, the function should return dom elements and the second argument for <code>el</code> is argument for given element.</p><!--<dde:mark type="component" name="example" host="this"/>--><divid="code-5abxx"class="example"><pre><codeclass="language-javascript">import { el } from "https://cdn.jsdelivr.net/gh/jaandrle/deka-dom-el/dist/esm-with-signals.js";
