sticky-scroll-mode

Sticky scroll mode is a minor mode to enable sticky scrolling in any buffer, language agnostic. If you'd prefer not to have a live sticky scroll window, and would rather have a temporary popup, you can use sticky-scroll-popup to briefly show the outer, offscreen context.

Example

Sticky scroll window

The package exposes the sticky-scroll--max-window-height which can be thought of as "the max number of outer contexts shown". If the sticky scroll buffer has more lines than sticky-scroll--max-window-height, only the last sticky-scroll--max-window-height are shown. Otherwise, the sticky window shows all lines.

Example

An outer context of:

A {
  B {
    C {

with a sticky-scroll--max-window-height of 2 will show:

  B {
    C {

sticky-scroll-popup

Pop up the sticky window until you do another command (moving, typing, etc.)

Compatible with C-u N, it will invoke the window as if sticky-scroll--max-window-height is set to N.

Approach

Uses an indentation approach, to find offscreen lines that are levels of indentation lower than the current point.

This works surprising well and quickly.

Known bugs

The sticky window disappears if you move to a 0-indent line that is within some indentation scope. Working on it.