const compose = (...fns) =>
fns.reduceRight((prevFn, nextFn) =>
(...args) => nextFn(prevFn(...args)),
value => value
);
Create the function, composed of three others:
const example = compose(
val => { console.log(1); return `1<${val}>`; },
val => { console.log(2); return `2<${val}>`; },
val => { console.log(3); return `3<${val}>`; }
);
Call the function:
example('hello')
Console output is:
3
2
1
"1<2<3<hello>>>"
Looks twisted, I agree with @nem035
It can simply be
const compose = (...fns) => fns.reduce((a,b) => (...val) => a(b(...val)))