command

id	behavioral/command
name	Command
aliases	action transaction
guide_url
problem	Package a request as an object so it can be queued, logged, undone, or executed later by code that doesn't know its details.
symptoms	undo/redo task queue macro recording button callbacks audit log of operations
verdict	use-with-care
caveats	If you only need 'execute later', a plain callable or functools.partial is the whole pattern — don't build a class hierarchy for a deferred call. The class form earns its keep exactly when commands carry extra behavior: undo(), serialization, or metadata.
stdlib_sightings	functools.partial sched.scheduler unittest.mock.call

Command

Package a request as an object so it can be queued, logged, undone, or run by code that doesn't know its details. Verdict: use with care — a callable is the whole pattern until commands need undo, logs, or metadata.

Where	What
pattern/	The importable code: Undoable, UndoStack, Action
docs/	Fundamentals · Implementation guide · External examples
examples/editor_undo/	Mini-project: text-editor undo/redo built on pattern/
tests/	Behavioral tests for the pattern and the mini-project

uv run python -m patterns.behavioral.command.examples.editor_undo.main