CodeMirror Indentation Markers

A CodeMirror extension that renders indentation markers using a
heuristic similar to what other popular editors, like Ace and Monaco, use.

!Example

$3

``ts
import { basicSetup } from 'codemirror';
import { EditorState } from '@codemirror/state';
import { EditorView } from '@codemirror/view';
import { indentationMarkers } from '@replit/codemirror-indentation-markers';

const doc =
def max(a, b):
if a > b:
return a
else:
return b

new EditorView({
state: EditorState.create({
doc,
extensions: [basicSetup, indentationMarkers()],
}),
parent: document.querySelector('#editor'),
});

`

$3

You can provide an options object to indentationMarkers() with the following
optional properties:

- highlightActiveBlock

Boolean that determines whether the active block marker is styled
differently. Setting this to false provides a significant performance
enhancement because it means that markers do not need to be regenerated
when the selection changes. Defaults to true.

- hideFirstIndent

Boolean that determines whether markers in the first column are omitted.
Defaults to false.

- markerType

String that determines how far the indentation markers extend. "fullScope" indicates that the markers extend down the full height of a scope. With the "codeOnly" option, indentation markers terminate at the last nonempty line in a scope. Defaults to "fullScope".

- thickness

Integer that determines the thickness in pixels of the indentation markers. Defaults to 1.

- activeThickness

Integer that determines the thickness in pixels of the active indentation markers. If undefined or null then thickness will be used. Defaults to undefined.

- colors

Object that determines the colors of the indentation markers.

- light

String that determines the color of the markers when the editor has a light theme. Defaults to #F0F1F2.

- dark

String that determines the color of the markers when the editor has a dark theme. Defaults to #2B3245.

- activeLight

String that determines the color of the active block marker when the editor has a light theme. Only applies if highlightActiveBlock is true. Defaults to #E4E5E6.

- activeDark

String that determines the color of the active block marker when the editor has a dark theme. Only applies if highlightActiveBlock is true. Defaults to #3C445C.

#### Example

`ts
new EditorView({
state: EditorState.create({
doc,
extensions: [
basicSetup,
indentationMarkers({
highlightActiveBlock: false,
hideFirstIndent: true,
markerType: "codeOnly",
thickness: 2,
colors: {
light: 'LightBlue',
dark: 'DarkBlue',
activeLight: 'LightGreen',
activeDark: 'DarkGreen',
}
})
],
}),
parent: document.querySelector('#editor'),
});
``