45 lines
1.2 KiB
JavaScript
45 lines
1.2 KiB
JavaScript
export const memoize = (provider, isExpired, requiresRefresh) => {
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let resolved;
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let pending;
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let hasResult;
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let isConstant = false;
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const coalesceProvider = async () => {
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if (!pending) {
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pending = provider();
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}
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try {
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resolved = await pending;
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hasResult = true;
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isConstant = false;
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}
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finally {
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pending = undefined;
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}
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return resolved;
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};
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if (isExpired === undefined) {
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return async (options) => {
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if (!hasResult || options?.forceRefresh) {
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resolved = await coalesceProvider();
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}
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return resolved;
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};
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}
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return async (options) => {
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if (!hasResult || options?.forceRefresh) {
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resolved = await coalesceProvider();
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}
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if (isConstant) {
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return resolved;
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}
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if (requiresRefresh && !requiresRefresh(resolved)) {
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isConstant = true;
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return resolved;
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}
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if (isExpired(resolved)) {
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await coalesceProvider();
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return resolved;
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}
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return resolved;
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};
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};
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