Emacs has always offered two camps when it comes to long lines: hard wrapping (inserting actual newlines at fill-column with M-q or auto-fill-mode) and soft wrapping (displaying long lines across multiple visual lines with visual-line-mode).1

Hard wrapping modifies the buffer text, which isn’t always desirable. Soft wrapping preserves the text but has always had one glaring problem: continuation lines start at column 0, completely ignoring the indentation context. This makes wrapped code and structured text look terrible.

Emacs 30 finally solves this with visual-wrap-prefix-mode.

What it does

When enabled alongside visual-line-mode, visual-wrap-prefix-mode automatically computes a wrap-prefix for each line based on its surrounding context. Continuation lines are displayed with proper indentation — as if the text had been filled with M-q — but without modifying the buffer at all.

The effect is purely visual. Your file stays untouched.

Basic setup

As usual, you can enable the mode for a single buffer:

(visual-wrap-prefix-mode 1)

Or globally:

(global-visual-wrap-prefix-mode 1)

You’ll likely want to pair it with visual-line-mode:

(global-visual-line-mode 1)
(global-visual-wrap-prefix-mode 1)

Note that with visual-line-mode soft wrapping happens at the window edge. If you’d like to control the extra indentation applied to continuation lines, you can tweak visual-wrap-extra-indent (default 0):

;; Add 2 extra spaces of indentation to wrapped lines
(setq visual-wrap-extra-indent 2)

Before and after

Without visual-wrap-prefix-mode (standard visual-line-mode):

    Some deeply indented text that is quite long and
wraps to the next line without any indentation, which
looks terrible and breaks the visual structure.

With visual-wrap-prefix-mode:

    Some deeply indented text that is quite long and
    wraps to the next line with proper indentation,
    preserving the visual structure nicely.

A bit of history

If this sounds familiar, that’s because it’s essentially the adaptive-wrap package from ELPA — renamed and integrated into core Emacs. If you’ve been using adaptive-wrap-prefix-mode, you can now switch to the built-in version and drop the external dependency.

Closing Thoughts

As mentioned earlier, I’m not into soft wrapping myself - I hate long lines and I prefer code to look exactly the same in every editor. Still, sometimes you’ll be dealing with some code you can’t change, and I guess many people don’t feel as strongly about cross-editor consistency as me. In those cases visual-wrap-prefix-mode will be quite handy!

I have to admit I had forgotten about auto-fill-mode before doing the research for this article - now I’m wondering why I’m not using it, as pressing M-q all the time can get annoying.

That’s all I have for you today. Keep hacking!

  1. I’ve always been in the M-q camp. ↩