20 lines
798 B
TypeScript
20 lines
798 B
TypeScript
// IndexedDB doesn’t support boolean indexes so we map `true` to 1 and `false`
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// to `0`, i.e. `IndexableBoolean`.
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// N.B. Using `undefined` allows excluding an entry from an index. Useful
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// when index size is a consideration or one only needs to query for `true`,
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// i.e. `IndexablePresence`.
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export type IndexableBoolean = IndexableFalse | IndexableTrue;
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export type IndexablePresence = undefined | IndexableTrue;
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type IndexableFalse = 0;
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type IndexableTrue = 1;
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export const INDEXABLE_FALSE: IndexableFalse = 0;
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export const INDEXABLE_TRUE: IndexableTrue = 1;
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export const toIndexableBoolean = (value: boolean): IndexableBoolean =>
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value ? INDEXABLE_TRUE : INDEXABLE_FALSE;
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export const toIndexablePresence = (value: boolean): IndexablePresence =>
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value ? INDEXABLE_TRUE : undefined;
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