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db240980a3
Currently the playground is setup as a linked workspace for the
compiler which complicates our yarn workspace setup and means that snap
can sometimes pull in a different version of react than was otherwise
specified.
There's no real reason to have these workspaces combined so let's split
them up.
ghstack-source-id: 56ab064b2f
Pull Request resolved: https://github.com/facebook/react/pull/31081
41 lines
1.1 KiB
TypeScript
41 lines
1.1 KiB
TypeScript
/**
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* Copyright (c) Meta Platforms, Inc. and affiliates.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*/
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import React from 'react';
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/**
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* Replacement to React.createContext.
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*
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* Does not take any default value and avoids non-null assertions when using
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* the value of the context, like the following scenario.
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*
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* ```ts
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* const StoreDispatchContext = useContext<Dispatch<ReducerAction>>(null);
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* const dispatchStore = useContext(StoreDispatchContext);
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* ...
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* dipatchStore!({ ... });
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* ```
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*
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* Instead, it throws an error when `useContext` is not called within a
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* Provider with a value.
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*/
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export default function createContext<T>(): {
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useContext: () => NonNullable<T>;
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Provider: React.Provider<T | null>;
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} {
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const context = React.createContext<T | null>(null);
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function useContext(): NonNullable<T> {
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const c = React.useContext(context);
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if (!c)
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throw new Error('useContext must be within a Provider with a value');
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return c;
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}
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return {useContext, Provider: context.Provider};
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}
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