Add a 'nextTick' function to dart:core

[DartBot]

This issue was originally filed by ladicek@gmail.com

---

If you want to defer execution of some function to a later turn of the event queue, you have to use Timer (from dart:io) on the VM and window.setTimeout (from dart:html) in the browser.

Now there is a bug to move Timer from dart:io to dart:core (and I think this should definitely be done), but using timer with zero timeout for deferring execution is quite inconvenient. I suggest to add a function like 'nextTick' to dart:core, modeled after Node.js's API (see http://nodejs.org/api/process.html#process_process_nexttick_callback).

1. It's more convenient.
2. The API would be the same in both environments.
3. As Node guys point out, it can be implemented much more efficiently (which apparently only applies to the VM, it would probably still be compiled to window.setTimeout for the browser).

I'm not exactly sure about the name, maybe 'deferExecution' or 'nextTurn' would be better, but I'll leave this decision up to you.

[sethladd]

FYI this came up on the mailing list

https://groups.google.com/a/dartlang.org/d/msg/misc/2Uc6cNDWNz0/JygYiaH9-ysJ

CC'ing Mads and Ivan, as this spans the IO lib and the VM (I think)

---

cc @madsager.
cc @iposva-google.
Removed Type-Defect label.
Added Type-Enhancement, Area-Library, Triaged labels.

[DartBot]

This comment was originally written by jim.b...@gmail.com

---

Please give it a better name. Next tick sounds so much like its related to the clock. Justin suggested "defer", which is much clearer.

[andersjohnsen]

Today we have two options for scheduling delaying tasks for immediate execution:

  Timer.run

and

  runAsync

both available in dart:async. The latter is scheduled for execution before any Timer and DOM events.

---

Added Fixed label.

[andersjohnsen]

Quick update, runAsync was renamed to scheduleMicrotask a few days ago. :)