Simple js compose

The concept of compose is simple — it combines n functions. It’s a pipe flowing right-to-left, calling each function with the output of the last one.

Array.prototype.reduceRight = function (...args) { const _this = this return _this.reverse().reduce(...args) } const compose = (...args) => x => args.reduceRight((acc, currFn)=>{ return currFn(acc) }, x) const double = x => x * 2 const inc = x => x + 1 const incAndOct = compose(double, double, double, inc) incAndOct(2) //24 

Explanation:

we are passing 2 to incAndOct function. First it will call inc method then the result will be 3 and next it will apply double method on 3 so result is 6 again one more double but this time on double(3) i.e 6 result is 12 now final double on 12 it is 24