How to automatically create 'Table of Contents' of a markdown text file in vim?

To use the Vim global command for lines containing only "===" or "---", the pattern needs to match the entire line content exactly.

Here is how to construct the pattern:

Code

:g/^\(===\|---\)/-1p

Explanation of the pattern:

• ^: This anchor matches the beginning of the line. It ensures that the pattern must start at the very beginning of the line.
• \(...\): This creates a capturing group for alternation.
• ===: This matches the literal string "===".
• \|: This is the OR operator within a regular expression. It allows matching either the pattern before it or the pattern after it.
• ---: This matches the literal string "---".
• \): This closes the capturing group.
• -1 : Print the line above the '===' line (or '---' line)
• p : Print