Uses of Fibers

[Deijin27]

This is a discussion of use cases of Fibers in Wren. They're obviously used for errors, but what are other times where they can be useful?

If you have ideas, please post a new sub-thread. I'll start with one I thought about.

[Deijin27]

Lazy Recursion

This example shows how you could use Fibers to iterate over a recursive
structure, without having to load everything into a list first.

class Directory {
  construct new() {
    _childDirs = []
    _files = []
  }
  childDirs { _childDirs }
  files { _files }
  filesRecurseFiber() {
    for (file in files) {
      Fiber.yield(file)
    }
    for (dir in childDirs) {
      dir.filesRecurseFiber()
    }
  }
}

var dir1 = Directory.new()
var dir2 = Directory.new()

dir1.files.add("fileA")
dir1.files.add("fileB")
dir2.files.add("fileC")
dir2.files.add("fileD")
dir1.childDirs.add(dir2)

var fiber = Fiber.new { dir1.filesRecurseFiber() }
while (true) {
  var file = fiber.call()
  if (fiber.isDone) break
  System.print(file)
}

[mhermier]

Faking a cooperative threads model. The idea is too yield some specific values a thread scheduler can react on, to simulate threads.