2018-04-13 20:25:52 +00:00
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/**
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* @prettier
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*/
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2018-04-12 21:19:13 +00:00
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// `missingCaseError` is useful for compile-time checking that all `case`s in
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// a `switch` statement have been handled, e.g.
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//
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// type AttachmentType = 'media' | 'documents';
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//
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// const type: AttachmentType = selectedTab;
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// switch (type) {
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// case 'media':
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// return <ImageThumbnail/>;
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// case 'documents':
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// return <DocumentListEntry/>;
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// default:
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// return missingCaseError(type);
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// }
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//
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// If we extended `AttachmentType` to `'media' | 'documents' | 'links'` the code
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// above would trigger a compiler error stating that `'links'` has not been
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// handled by our `switch` / `case` statement which is useful for code
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// maintenance and system evolution.
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export const missingCaseError = (x: never): TypeError =>
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new TypeError(`Unhandled case: ${x}`);
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