17 lines
360 B
JavaScript
17 lines
360 B
JavaScript
export function nameSpacedTransformer(ns, transformer) {
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if (!transformer) {
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return nameSpacedTransformer.bind(null, ns);
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}
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return (state) => {
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const newState = transformer(state[ns]);
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// nothing has changed
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// noop
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if (!newState || newState === state[ns]) {
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return null;
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}
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return { ...state, [ns]: newState };
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};
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}
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