Note: This package only works for the erlang target.
This is a simple gleam library that adds a iterator_pmap and list_pmap,
which has a similar behaviour and interface as iterator.map and list.map,
except it runs in parallel by spawning extra processes to do the work.
There is also iterator_find_pmap and list_find_pmap which stop the whole
parallel execution after finding the first Ok value.
gleam add parallel_mapimport gleam/list
import gleam/iterator
import gleam/result
import parallel_map.{MatchSchedulers, WorkerAmount}
pub fn main() {
let map_func = fn(a: Int) -> Int {a * a}
let iterator_input = iterator.range(0, 1000)
iterator_input
|> iterator.map(map_func)
// can be rewritten as
iterator_input
|> parallel_map.iterator_pmap(map_func, WorkerAmount(16), 100)
|> iterator.map(result.unwrap(_, -1))
let list_input = list.range(0, 1000)
list_input
|> list.map(map_func)
// can be rewritten as
list_input
|> parallel_map.list_pmap(map_func, MatchSchedulersOnline, 100)
|> list.map(result.unwrap(_, -1))
// there is also
// parallel_map.iterator_find_pmap similar to iterator.find_map
// parallel_map.list_find_pmap similar to list.find_map,
// which stop the works after finding the first Ok value.
let find_map_func = fn(a: Int) -> Result(Int, Int) {
case a {
x if x > 500 -> Ok(x * 2)
_ -> Error(a)
}
}
iterator_input
|> iterator.find_map(find_map_func)
// can be rewritten as
iterator_input
|> parallel_map.iterator_find_pmap(find_map_func, WorkerAmount(16), 100)
list_input
|> list.find_map(find_map_func)
// can be rewritten as
list_input
|> parallel_map.list_find_pmap(find_map_func, MatchSchedulersOnline, 100)
}Further documentation can be found at https://hexdocs.pm/parallel_map.
gleam run # Run the project
gleam test # Run the tests
gleam shell # Run an Erlang shell