md`# Function Composition
Prompt: Create a javascript function which takes in a bunch of function as arguments and performs left to right composition on them. It then returns the result from a function which takes in a single argument on which it performs the composition.
## Approach 1: Currying and closures
`
compose = (...funcs) => {
return n => {
let result
funcs.forEach(func => {
result = func(result || n)
})
return result
}
}
md`## Approach 2: Reduce
`
composeViaReduce = (...fns) => val => fns.reduce((acc, fn) => fn(acc), val)
md `# Tests`
addOne = num => num + 1
substractTwo = num => num - 2
multiplyThree = num => num * 3
ltrComposition = compose(addOne, substractTwo, multiplyThree)
result = ltrComposition(4)
compose(addOne, substractTwo, multiplyThree)(5)
composeViaReduce(addOne, substractTwo, multiplyThree)(5)
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