July 4, 2019

1745 words 9 mins read

susam/mdme

susam/mdme

Self-rendering Markdown content

repo name susam/mdme
repo link https://github.com/susam/mdme
homepage
language JavaScript
size (curr.) 57 kB
stars (curr.) 137
created 2018-10-26
license MIT License

MdMe

MdMe (pronounced em-dee-me) is a lightweight JavaScript utility to create self-rendering Markdown documents.

View Demo Build Status Coverage Status NPM Version MIT License

MdMe is a stripped down fork of TeXMe. While TeXMe renders both Markdown and LaTeX content, MdMe renders Markdown only. Thus MdMe is smaller, lighter, and simpler than TeXMe, and a good choice for writing Markdown-only (no LaTeX) documents.

Contents

Get Started

Content in Textarea

Copy and paste the code below into an HTML file with .html as the extension name:

<!DOCTYPE html><script src="https://cdn.jsdelivr.net/npm/mdme@0.3.0"></script><textarea>

# Atomic Theory

**Atomic theory** is a scientific theory of the nature of matter, which
states that matter is composed of discrete units called *atoms*. It
began as a philosophical concept in ancient Greece and entered the
scientific mainstream in the early 19th century when discoveries in the
field of chemistry showed that matter did indeed behave as if it were
made up of atoms.


## John Dalton

Dalton believed atomic theory could explain why water absorbed different
gases in different proportions - for example, he found that water
absorbed carbon dioxide far better than it absorbed nitrogen.


## See Also

See the Wikipedia article on [Atomic
Theory](https://en.wikipedia.org/wiki/Atomic_theory) for more details.

This file contains one line of HTML code followed by Markdown content.

Open this HTML file with a web browser. It renders itself to look like this: content-in-textarea.html.

There are two simple rules to remember while using MdMe:

  • MdMe removes any leading and trailing whitespace in the content before rendering the content to HTML.
  • TeXMe uses the first non-empty line of the content to set the page title if no explicit <title> element is specified. Any leading and trailing whitespace and hash (#) characters are removed while setting the page title.

Content in Body

If you do not like to start your document with HTML tags, you can write your content first and add the <script> tag in the end like this:

# Atomic Theory

**Atomic theory** is a scientific theory of the nature of matter, which
states that matter is composed of discrete units called *atoms*. It
began as a philosophical concept in ancient Greece and entered the
scientific mainstream in the early 19th century when discoveries in the
field of chemistry showed that matter did indeed behave as if it were
made up of atoms.

<script src="https://cdn.jsdelivr.net/npm/mdme@0.3.0"></script>

Here is the output: content-in-body.html.

Although, the code looks neater in this example, there is a limitation associated with this form of writing content: Since the content is part of the HTML <body> element (there is no <textarea> element in this code), the content should be written carefully, so that it does not have any HTML syntax error. See the Caveats section of the TeXMe documentation for more details about this.

CDN URLs

Use the following URL in the <script> tag to load version 0.3.0 (the current version at this time) of MdMe:

https://cdn.jsdelivr.net/npm/mdme@0.3.0

Use the following URL in the <script> tag to always load the latest version of MdMe:

https://cdn.jsdelivr.net/npm/mdme

If you need something really easy to remember, use this URL to load the latest version of MdMe:

https://unpkg.com/mdme

Valid HTML5

The “get started” example in the previous section attempts to show how we can create a self-rendering document with a single line of HTML code but this brevity comes at the cost of standard conformance. For example, the required <title> element is missing from the code. Further the <textarea> element is not closed.

For the sake of completeness and correctness, here is a minimal but complete and valid HTML5 example:

<!DOCTYPE html>
<html lang="en">
<title>Notes on Atomic Theory</title>
<script src="https://cdn.jsdelivr.net/npm/mdme@0.3.0"></script>
<textarea>

# Atomic Theory

**Atomic theory** is a scientific theory of the nature of matter, which
states that matter is composed of discrete units called *atoms*. It
began as a philosophical concept in ancient Greece and entered the
scientific mainstream in the early 19th century when discoveries in the
field of chemistry showed that matter did indeed behave as if it were
made up of atoms.

</textarea>

Here is the output: valid-html5.html.

It has a few more lines of code to ensure that this HTML5 code validates successfully at validator.w3.org. As a result, this example does not look as concise as the one in the previous section.

In case you are wondering, a valid HTML5 document does not require explicit <head>, <body>, or the closing </html> tags. So they have been omitted for the sake of brevity while maintaining completeness and correctness.

In practice though, it is not necessary to write verbose code like this. All browsers follow the robustness principle, so they can render the shorter example in the previous section just fine.

Use MdMe in Web Pages

Style

MdMe renders the document on a white pane against a gray background by default. This is due to a configuration option named style that is set to 'viewer' by default.

To render the document with a minimal style on a completely plain white background, set the style configuration option to 'plain'. Here is an example:

<!DOCTYPE html>
<script>window.mdme = { style: 'plain' }</script>
<script src="https://cdn.jsdelivr.net/npm/mdme@0.3.0"></script><textarea>

# Atomic Theory

**Atomic theory** is a scientific theory of the nature of matter, which
states that matter is composed of discrete units called *atoms*. It
began as a philosophical concept in ancient Greece and entered the
scientific mainstream in the early 19th century when discoveries in the
field of chemistry showed that matter did indeed behave as if it were
made up of atoms.

Here is the output: style-plain.html.

To render the document with absolutely no style, set style to 'none'. The 'none' style option is useful to disable the default 'viewer' style set by MdMe before defining a custom style with regular CSS code. Here is an example:

<!DOCTYPE html>
<script>window.mdme = { style: 'none' }</script>
<script src="https://cdn.jsdelivr.net/npm/mdme@0.3.0"></script>
<style>
body {
  background: lightcyan;
}
main {
  max-width: 20em;
  padding: 1em;
  border: medium double gray;
  margin: 2em auto;
  background: lightyellow;
}
</style>
<textarea>

# Atomic Theory

**Atomic theory** is a scientific theory of the nature of matter, which
states that matter is composed of discrete units called *atoms*. It
began as a philosophical concept in ancient Greece and entered the
scientific mainstream in the early 19th century when discoveries in the
field of chemistry showed that matter did indeed behave as if it were
made up of atoms.

Here is the output: style-custom.html.

Note that the rendered content is displayed within a <main> element inside the <body>. That is why these elements are being styled in the above example.

Skip Automatic Rendering on Load

When MdMe loads, it begins rendering the document automatically. This automatic rendering may be skipped by setting renderOnLoad option to false. Here is an example that disables automatic rendering and then invokes rendering later on the click of a button by using the mdme.renderPage() function from the MdMe API:

<!DOCTYPE html>
<script>window.mdme = { renderOnLoad: false }</script>
<script src="https://cdn.jsdelivr.net/npm/mdme@0.3.0"></script>
<script>
window.onload = function () {
  var button = document.getElementById('button')
  button.onclick = function () {
    button.remove()
    mdme.renderPage()
  }
}
</script>
<textarea>

# Atomic Theory

**Atomic theory** is a scientific theory of the nature of matter, which
states that matter is composed of discrete units called *atoms*. It
began as a philosophical concept in ancient Greece and entered the
scientific mainstream in the early 19th century when discoveries in the
field of chemistry showed that matter did indeed behave as if it were
made up of atoms.

</textarea>
<div><button id="button">Render</button></div>

Here is the output: skip-render.html.

Set Options After Loading

When we load MdMe with the <script> tag, it begins rendering the document as soon as it loads. Therefore in the above examples, we define the configuration options prior to loading MdMe. We do this by defining an object named window.mdme with the configuration options defined as properties in this project.

However if we set the renderOnLoad option to false, we prevent MdMe from rendering the document after it loads. We now have the control to invoke the rendering at a later time, e.g., on the click of a button. In this case, it is possible to set configuration options after loading MdMe with the mdme.setOption() function. This function takes two parameters: option name as a string and option value.

Here is an example that skips automatic rendering on load and sets the style to 'plain' using this function:

<!DOCTYPE html>
<script>window.mdme = { renderOnLoad: false }</script>
<script src="https://cdn.jsdelivr.net/npm/mdme@0.3.0"></script>
<script>
window.onload = function () {
  var button = document.getElementById('button')
  button.onclick = function () {
    button.remove()
    mdme.setOption('style', 'plain')
    mdme.renderPage()
  }
}
</script>
<textarea>

# Atomic Theory

**Atomic theory** is a scientific theory of the nature of matter, which
states that matter is composed of discrete units called *atoms*. It
began as a philosophical concept in ancient Greece and entered the
scientific mainstream in the early 19th century when discoveries in the
field of chemistry showed that matter did indeed behave as if it were
made up of atoms.

</textarea>
<div><button id="button">Render</button></div>

Here is the output: set-options.html.

Configuration Options

Here is a quick reference for all the supported configuration options:

  • style ('viewer' by default): Three values are supported: 'viewer', 'plain', and 'none'. The viewer style displays the rendered document on a white pane against a gray background. The plain style displays the content with a very minimal style that does not change the background style. If set to 'none', no style whatsoever is applied and the document is displayed with the browser’s default style.

  • renderOnLoad (true by default): Begins rendering the document automatically on load when set to true. Skips rendering automatically when set to false.

  • onRenderPage (undefined by default): A callback function that is automatically invoked after MdMe completes rendering the page. It is guaranteed that MdMe has completed rendering the page before invoking this callback.

  • commonmarkURL (CDN URL of minified commonmark.js, i.e., commonmark.min.js, version 0.28.1 by default): URL to load commonmark.js while running in a web browser.

License

This is free and open source software. You can use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of it, under the terms of the MIT License. See LICENSE.md for details.

This software is provided “AS IS”, WITHOUT WARRANTY OF ANY KIND, express or implied. See LICENSE.md for details.

Support

To report bugs, suggest improvements, or ask questions, create issues.

comments powered by Disqus