larryyangsen
larryyangsen
/ createCtx-noNullCheck.tsx
Created
March 3, 2020 01:38
— forked from swyxio/createCtx-noNullCheck.tsx
better createContext APIs with setters, and no default values, in Typescript. this is documented in https://github.com/typescript-cheatsheets/react-typescript-cheatsheet/blob/master/README.md#context
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| // create context with no upfront defaultValue | |
| // without having to do undefined check all the time | |
| function createCtx<A>() { | |
| const ctx = React.createContext<A | undefined>(undefined) | |
| function useCtx() { | |
| const c = React.useContext(ctx) | |
| if (!c) throw new Error("useCtx must be inside a Provider with a value") | |
| return c | |
| } | |
| return [useCtx, ctx.Provider] as const |