point-free.R

compose_right_to_left <- function(funs) function(x) Reduce(function(y, f) f(y), funs, x)

some_composition <- compose_right_to_left(list(cumsum, sqrt, log))

# cumsum(sqrt(log(16:35))), these are all vectorized and return length n output 
some_composition(16:35)

# Creates a function that takes in a list of functions and returns a function
# that applies those functions to an input argument 'value'. These functions can `reduce` (sum)
# or apply a potentially vectorized operation (`log`, `sqrt`, etc) in whatever order you want.
# Ex list(sum, sqrt, log) will take log of all entries, then sqrt of that result and finally sum up to one number
compose_right_to_left <- function(funs) {
  function(value) {
    Reduce(function(y, f) f(y), funs, value)
  }
}