Templater

Simple, client side vanilla javascript way to have includes for template html files.

A primitive, client side templating system.

A combination of javascript's template literals (backticks), eval() and fetch() (or via XMLHttpRequest methods) makes client side html includes of html snippet files with variable expansion possible.

V1.2.1 : Has includes inside template files working and a first try at evaluation of javascript in template files.

In your primary html file, say index.html, at the bottom in the body tag, import and instantiate the Templater class:

<script type="module">
    // import { Templater as Templater }   from './assets/javascript/modules/src/templater.js';// easier:
    import { Templater as Templater }   from 'https://unpkg.com/@wowter/[email protected]/assets/javascript/modules/src/templater.js';
    const templaterInstance = new Templater();
</script>

To have an include, add a html tag with attribute data-include containing the path to the inclusion file:

<div data-include="./templates/top.tmpl.html"></div>

If you wish to use variables for expansion of place holders in inclusion files, at the top in the body tag add a html tag with attrribute data-variables, containing a string with a json object:

<div data-variables='{
    "mainCase": "Whoopsie Daisies.", 
    "subCase": "Rimbo De Rukker.", 
    "subSubCase": "Down the great Belows.",
    "bgcolor": "burlywood"
    }'>
</div>

Now create html snippet files (without html, body and head tags) that will be your inclusion files. Inside your inclusion files place holders can be used:

<div>
    ${variables.mainCase}
    For the subsubdueds!
</div>

In the place holder indication ${ } variables.mainCase references "Woopsie Daises.", and will expand as such:

<div>
    Woopsie Daises.
    For the subsubdueds!
</div>

Inclusion files are not restricted to html files:

<style data-include="./templates/main.tmpl.css"></style>

with main.tmpl.css containing

body {
    background-color: ${variables.bgcolor};
}

will work.

The javascript code inside script tags, or files referenced in src attribute in template files are passed through eval, but no real testing was done yet.

See:
https://developer.mozilla.org/nl/docs/Web/JavaScript/Reference/Template_literals
https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API/Using_Fetch