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@sumanbh
sumanbh / createCtx-noNullCheck.tsx
Created July 4, 2019 20:17 — forked from swyxio/createCtx-noNullCheck.tsx
better createContext APIs with setters, and no default values, in Typescript
// 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