@impjs/impjs

almost-js

WORK IN PROGRESS

A templating engine using as much as possible of what the JavaScript language gives (especially template literals).

Templates are plain JavaScript files whose last non-function statements are returned and formatted into a String.

This allows various things:

// Explicitely require the necessary helpers
// instead of losing which are used in a global 
// list of helpers. It also avoid naming collisions
// between helpers
const {escape} = require('./html')

// Some pre-processing of the template data
// right next to the code rendering it
// (Admitedly the following chunk of code could
// well be in its own helper)
const htmlAttributes = Object.entries(attributes).map(([name,value] => `name=${escape(value)}`)).join(' ');

// Use regular template literals to generate the resulting HTML
`<article ${htmlAttributes}>
  <h1>${post.title}</h1>
  ${() => {
    // Function expressions are automatically evaluated
    // Allowing to use plain Javascript `if`
    if (post.excerpt) {
      // Their last statement is automatically returned
      // to not cluter the template with `return`
      post.excerpt
    }
  }}
  ${tagList(post)}
</article>`

// Chunkier part of the template can be extracted
// in their own function
function tagList(post) {
  `<ul>
    ${() => {
      // Just like `if`, `for` loops' final statements get returned
      for(var i = 0; i < post.tags.length; i++) {
        const tag = post.tags[i];
        `<li><a href="/tags/${tag.slug}">${tag.name}</a></li>`
      }
    }}
  </ul>`
}

TODO

• [ ] Add option for customizing Babel configuration
• [ ] Maybe rename the express template engine to expressTemplateEngine rather than the more obscure __express