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'use strict';

const compose = (...fns) => (x) => {

if (fns.length === 0) return x;

const fn = fns.pop();

const res = fn(x);

return compose(...fns)(res);

};

const pipe = (...fns) => (x) => {

if (fns.length === 0) return x;

const fn = fns.shift();

const res = fn(x);

return pipe(...fns)(res);

};

// Usage

const upperFirst = (word) => word.charAt(0).toUpperCase() + word.slice(1);

const upperCapital = (s) => s.split(' ').map(upperFirst).join(' ');

const lower = (s) => s.toLowerCase();

const trim = (s) => s.trim();

const s = ' MARCUS AURELIUS ';

console.log(s);

console.log(`lower('${s}') = '${lower(s)}'`);

console.log(`upperCapital('${s}') = '${upperCapital(s)}'`);

{

console.log('Use compose');

const capitalize = compose(upperCapital, lower, trim);

console.log(`capitalize('${s}') = '${capitalize(s)}'`);

}

{

console.log('Use pipe');

const capitalize = pipe(trim, lower, upperCapital);

console.log(`capitalize('${s}') = '${capitalize(s)}'`);

}