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I understand that there is some controversy about the name of setImmediate. Does anyone know if this useful functionality will make it into V8/Spider Monkey any time soon, regardless of name?

Ben Aston
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  • Isn't it analogous to `setTimeout(funcRef, 0);`? Am I missing something? – crush Aug 17 '15 at 19:32
  • `setTimeout(funcRef, 0);` [clips to 4ms](https://stackoverflow.com/a/9647221/2039244). Presumably `setImmediate` would not. [Interesting article on this subject](http://www.nczonline.net/blog/2011/09/19/script-yielding-with-setimmediate/). – sdgluck Aug 17 '15 at 19:36
  • If the task runs immediately, what's the sense in returning an ID that can be cancelled? And is 4ms timer resolution really that big of a deal? – crush Aug 17 '15 at 19:41
  • A 1GHz CPU can perform 4 million operations in 4ms (at least). Which may or may not be a big deal depending on your use-case. – Ben Aston Aug 17 '15 at 19:46
  • @BenAston The 15.6ms timer resolution seems like it would be a big deal, but 4ms doesn't seem like it would be enough of a difference to noticeably slow the UI. Assuming that at 0ms setImmediate would pause the thread for nanoseconds each time such a task ran, couldn't you just quadruple these operations up? Would you really notice the impact on the UI thread between 4 and 0 ms? – crush Aug 17 '15 at 20:10

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https://developer.mozilla.org/en-US/docs/Web/API/Window/setImmediate:

Note: This method is not expected to become standard, and is only implemented by recent builds of Internet Explorer and Node.js 0.10+. It meets resistance both from Gecko (Firefox) and Webkit (Google/Apple).

CBroe
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    So, that's a no, then? It seems that this is a missing feature in those browsers then. setTimeout has a wait time (4ms?) specified in the standard IIUC. Without setImmediate (or at the very least nextTick) there is no clean way to achieve asynchronous behavior without the 4ms noop. – Ben Aston Aug 17 '15 at 19:36
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    No clean way; although there are polyfills for it … check the article @sdgluck mentioned already, http://www.nczonline.net/blog/2013/07/09/the-case-for-setimmediate/ for some broader information on the topic. – CBroe Aug 17 '15 at 20:25