¬ just serendipity 🍀 (not just serendipity)

Previously.

I’ve been in love with watchexec:

Recursively monitors the current directory for changes, executing the command when a filesystem change is detected (among other event sources). By default, watchexec uses efficient kernel-level mechanisms to watch for changes.

It’s a modern version of entr.

Its usage is very simple and easy to remember:

watchexec [--clear] [--] python main.py

…will re-run python main.py whenever it changes on disk.

--clear will clear the screen between successive runs.

Other useful invocations:

watchexec make
watchexec just
watchexec -e html,css,js make  # watch the given extensions for changes
watchexec -w src make          # watch the given directory

There are various other useful command-line switches, its man page is very descriptive.

Here is a practical example when iterating on stack.py:

% watchexec --clear -- python stack.py
[Running: python stack.py]
[Command was successful]

% watchexec --clear -- ty check
[Running: ty check]
[Command was successful]

Alternative: fswatch.