switch without statement

tags: learning go programming

content

we have:

func (m *Model) Update(msg tea.Msg) (Model, tea.Cmd) {
	keyMsg, ok := msg.(tea.KeyMsg)
	if !ok {
		return m, nil
	}
	switch {
	case key.Matches(keyMsg, SomeKey):
		// do something
	default:
		// do something
	}
	return m, nil
}

in this code, there’s nothing after the switch
what is it switching on then??
- it’s not switching on anything!
- it’s the same as switch true!
because key.Matches() returns a bool, that’s what’s being switched on
- any true from key.Matches(keyMsg, SomeKey) will be the code path
it’s the same as:

keyMsg, ok := msg.(tea.KeyMsg)
if !ok {
	return m, nil
}
if key.Matches(keyMsg, SomeKey) {
	// do something
	return
}
if key.Matches(keyMsg, SomeOtherKey) {
	// do something
	return
}
// do something
return

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