Reduce a list to a single value by iteratively applying a binary function

Inspired by reduce() from the purrr package

reduce(.x, .f, ..., .init)

Arguments

.x: A list or atomic vector.
.f: A 2-argument function. The function will be passed the accumulated value as the first argument and the "next" value as the second argument.
...: Additional arguments passed on to .f.
.init: If supplied, will be used as the first value to start the accumulation, rather than using x[[1]]. This is useful if you want to ensure that reduce returns a correct value when .x is empty. If missing, and x is empty, will throw an error.

Jonathon Love jon@thon.cc