Delete a section by its heading

Goal: Drop a section you no longer want (e.g. remove a “Deprecated” section before publishing docs) while leaving the rest of the document intact.

Prerequisites: The section module, via -A or nodes.

Query

$ mq -A 'section::filter_sections(fn(s): section::title(s) != "Deprecated";)' README.md

Or with nodes:

import "section"
| nodes
| section::filter_sections(fn(s): section::title(s) != "Deprecated";)

Input

# Introduction

Welcome to the project.

## Installation

Run the following command.

## Deprecated

Do not use this anymore.

Output

# Introduction

Welcome to the project.

## Installation

Run the following command.

Notes

• filter_sections keeps a section when the predicate returns true, so the same pattern works for any condition, e.g. matching against a list of titles to drop, instead of a single != check.
• section::collect (flattening section objects back to plain Markdown nodes) isn’t needed here. mq expands section objects to Markdown automatically in query output. It’s only required when consuming section objects from Rust or other embedding code; see the equivalent note in Extract a section by its heading.