[flipdot]

I find the Compose feature to be quite useful, so I used to have Compose key on Caps Lock on Linux. After I’ve switched back to Windows, I found WinCompose to be a pretty decent equivalent of Compose for Windows, and found out it can also override Caps Lock behaviour (though in about 1% of cases the default Windows Caps Lock behaviour breaks through for a brief moment) and reassign the Caps Lock function to some other, less frequent combination of keys. In my case pressing both Shifts at the same time acts as a Caps Lock toggle.

[solardev]

What is a compose feature?

(edit: looked it up, and it seems to be a way to enter accented keyboard characters like é or ñ. It's standard on macos, and I guess in Linux you bind a key to it?)

[seabass-labrax]

It allows you to access more characters than would usually be accessible on the keyboard, such as diacritical marks and currency symbols.

[solardev]

Thanks! Sounds like the opt key on Macs or the AltGr key on some international keyboards

[Brian_K_White]

Just another form of shift key. Shift itself is a compose key.

[jgtrosh]

Not really: shift must be used simultaneously and you only input a single key to be shifted, while compose takes a (“dead”?) sequence of inputs to be combined.

[Brian_K_White]

yes really. it's all the same thing. shift is just a simpler and more common subset. you are getting a glyph by composing from more than one key. whether ypu can let go of the key to do them in serial is immaterial. anyone could have an accessability setup for instance that allows shift to require only a single physical keypress at a time. It would still be shift.

[stvltvs]

How can I input ° for example with Shift?

It's "AltGr o o" but I haven't seen how to do it with Shift.

[Brian_K_White]

It's immaterial if some key on some keyboard in some language happens to have a key that produces that glyph by composing with shift, or not.

If you asked how to type numbers, and I said "same way you type letters", that does not mean by typing "A" and wondering why it didn't produce "1".

The question was what is a compose key or what does compose key mean.

Shift is an example of a compose key that everyone is familar with, just no one calls it that. But everyone already understands what the shift key does. If you know what the shift key is and how to use it and what it does, then you know what a compose key is. It's that.

All the other possible compose keys just do exactly that same thing, just more of it for more and different glyphs and control codes.

[db48x]

You’ve misunderstood. No one said that they were equivalent, only that there was no functional difference between them. They certainly allow you to access different characters, but whether you hold down shift and then type a “d” to input a capital “D” or you tap shift and then tap the “d” to get the same result is merely a software setting that you can toggle. The same is true for AltGr and compose keys. You can configure your OS to require them to be typed as chords or as dead keys, whichever you prefer.

See also the space–cadet keyboard (<https://en.wikipedia.org/wiki/Space-cadet_keyboard#/media/Fi...>), which had no fewer than seven such keys labeled control, meta, super, hyper, shift, front, and top.