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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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About the <head>

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Insecure Resource

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CSS

About CSS Preprocessors

CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.

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HTML 

              
                <div class="mdl-layout__container">
  <div class="mdl-grid mdl-grid__max-width">
    <div class="mdl-card mdl-card__wide mdl-shadow--4dp">
      <div class="mdl-card__title mdl-color--accent">
        <h2 class="mdl-card__title-text">Functional App</h2>
      </div>
      <div id="post-container" class="mdl-card__supporting-text">
        <div class="mdl-progress mdl-js-progress mdl-progress__indeterminate"></div>
      </div>
    </div>
  </div>
</div>
!

CSS 

              
                .mdl-layout {
  &__container {
    margin-top: 2em;
    margin-bottom: 2em;
  }
}

.mdl-grid {
  &__max-width {
    max-width: 640px;
    margin: auto;
  }
}
.mdl-card {
  &__wide {
    width: 100%;
  }
}
!

JS 

              
                const {curry, compose, map} = R
// pure
const url      = "https://www.avanzu.de/wp-json/wp/v2"
const postsUrl = _ => `${url}/posts`
const join     = x => x.join('')
const prop     = s => obj => obj[s]
const theTitle = compose(prop('rendered'), prop('title'))
const span     = s => `<span class="mdl-list__item-primary-content">${s}</span>`
const li       = s => `<li class="mdl-list__item">${s}</li>`
const ul       = s => `<ul id="post-list" class="mdl-list">${s}</ul>`
const listItem = compose(li, span)
// impure 
const fetchJson  = fn => url => $.getJSON(url).then(fn)
const setHtml    = el => html => $(el).html(html)
const inspect    = label => x => (console.log(label, x), x)
// specialization 
const updatePostContainer = setHtml('#post-container')
const titleToList = map(compose(listItem,theTitle))
// app composition 
const render       = compose(updatePostContainer, ul, join, titleToList)
const executeApp   = compose(fetchJson(render), postsUrl)
// run the app
executeApp()
!
999px

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