How could I develop some new plugins in marp-vscode ?

[greyovo]

I have cloned the repo marp-vscode and run it with ease. I wanted to add some features for it e.g. a multi-column layout. Actually I did it, by writing some code directly in the src/extensions.ts using marp.use() interface as shown in the figure below:

But now the point is that, it looks a mess if I add the plugin code here. I do find some already written plguins in src/plugins, like custom-theme.ts, line-number.ts. I tried to write one more plugin like them but I just have no idea what's the runtime-type of the instance (see code below) and I dont know how to go next.

// copied from `src/plugins/custom-theme.ts`
export default function marpVSCodeCustomTheme(instance) {
  const { marpit, parse } = instance
  const registeredThemes = [...marpit.themeSet.themes()].map((t) => t.name)
  instance.parse = (...args) => {
    // ...
  }
}

Could u please tell me, how I can implement a new plugin like the code below, using markdownItContainer and its params?

Best regards. :)

[yhatt]

Marp.use() (Marpit.use()) is compatible with MarkdownIt.use(). See markdown-it API documentation.

MarkdownIt.use(plugin, params)

Load specified plugin with given params into current parser instance. It's just a sugar to call plugin(md, params) with curring.

— https://markdown-it.github.io/markdown-it/#MarkdownIt.use

So marp.use(plugin, ...args) is exactly same as calling plugin(marp.markdown, ...args). marp.markdown is a markdown-it instance managed by Marp instance (https://marpit-api.marp.app/marpit#markdown). From the markdown-it instance, you can access Marp (Marpit) class instance through md.marpit too.