Caching this in a ref to mitigate against spamming the keys raised in #831 (comment)

We should make the API consistent with RadioGroup and CheckboxGroup - they don't have the .Item part but use Radio.Root and Checkbox.Root

I started off doing that but in the end it was more practical to have this Item subcomponent, let me look up what the actual problem was

@colmtuite is this an issue for you?

The main issue was, if there wasn't the ToggleButtonGroup.Item component, the value becomes optional for ToggleButton.Root, even when it's in a toggle group

With the separate .Item, it's easier to ensure all toggle buttons in a group have a value

Unlike Accordion/Tabs, it makes less sense to not provide your own value and use the index position fallback value (it would still work 🤷 )

We decided to align the API with RadioGroup/CheckboxGroup for consistency, as it's relatively easy for users to enforce a required value for toggle buttons inside a group themselves
2d8ec7e

Make the hook parameters mandatory (per #856). Defaults should be set on the component level.

Updated ~ f715087

It might be better DX if the type of the value was an array only when toggleMultiple is set.
For parity with RadioGroup, we should allow any type of value.

For the value, I think it might be easier to remember (or harder to do something wrong) if it was always an array, if not we'd have to do a warning or something if you get the type wrong here

What do you think @atomiks @vladmoroz ?

It might be better DX if the type of the value was an array only when toggleMultiple is set.

Radix does this (different value type for accordion and toggle group based on whether they accept multiple items) and every single time I've created a wrapped accordion component for a design system it's been painful. You can't just pass props around without getting into some weird dance trying to please TypeScript

I said this about asChild and will maintain throughout that we should design our API without conditional types. They make sense on the surface but harm the DX more than they help you.

So yeah I really like always having an array as a value.

We discussed this and decided to avoid conditional types in general

For parity with RadioGroup, we should allow any type of value.

Updated ~ 98746a3