24 lines
457 B
JavaScript
24 lines
457 B
JavaScript
import arityN from 'arity-n';
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let compose2 = (f, g) => (...args) => f(g(...args));
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export default function compose(...functions) {
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const funcs = functions.filter(fn => typeof fn === 'function');
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let lastIdx = funcs.length - 1;
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let arity = 0;
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if (funcs.length <= 0) {
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throw new Error('No funcs passed');
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}
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if (lastIdx >= 0 && funcs[lastIdx]) {
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arity = funcs[lastIdx].length;
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}
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return arityN(funcs.reduce(compose2), arity);
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}
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