help with generics

[scarlet marten]

piscopancer#0

Playground Link

Preview:```ts
function useTabs<Tabs extends string[]>({
initTab,
tabs,
}: {
initTab: Tabs[number]
tabs: Tabs
}) {}

const x = useTabs({
initTab: "",
tabs: ["security", "appearance", "profile"],
})```

You can choose specific lines to embed by selecting them before copying the link.

[frosty rover]

...what's your question?

what do you need help with?

[distant chasm]

oh yes, totally forgot about it. I want initTab to be narrowed as security or appearance or profile

[scarlet marten]

that_guy977#0

Playground Link

Preview:```ts
function useTabs<const Tabs extends readonly string[]>({initTab, tabs}: {initTab: Tabs[number], tabs: Tabs}) {

}

const x = useTabs({initTab: '', tabs: ['security', 'appearance', 'profile']})```

You can choose specific lines to embed by selecting them before copying the link.

[distant chasm]

omg I have never seen you could put const and readonly inside a generic what the freaking hell

[frosty rover]

keep in mind that Tabs could be manually specified, so initTab may not be in tabs.

[scarlet marten]

that_guy977#0

Playground Link

Preview:```ts
function useTabs<const Tabs extends readonly string[]>({initTab, tabs}: {initTab: Tabs[number], tabs: Tabs}) {

}

const x = useTabs<string[]>({initTab: '', tabs: ['security', 'appearance', 'profile']})```

You can choose specific lines to embed by selecting them before copying the link.

[frosty rover]

readonly is part of the constraint, a readonly array means tuples are allowed.
const is a relatively new feature, it makes the generic attempt to infer a literal (more strongly, i think? i don't remember the specifics)

[distant chasm]

thank you, superhuman

!resloved