Passing Method into SetTimeOut using CoffeeScript

Question

This is my CoffeeScript code.

setTimeout (-> @checkProgress()), 5000

When I run this in the browser I get the following error:

TypeError: this.checkProgress is not a function

The method looks like:

checkProgress: ->
    ~ code
    ~ code
    ~ code
    setTimeout (-> @checkProgress()), 5000

So at some point I want to call the method again. How can I do this? Thanks.

@checkProgress is already a function. You do not need to wrap it in another function. Just use setTimeout @checkProgress, 5000 — Ruslan
– Ruslan, Commented Aug 11, 2016 at 4:10
In other cases you can use helper: delay = (t, fn) -> setTimeout(fn, t). — Ruslan
– Ruslan, Commented Aug 11, 2016 at 4:12
That's what I was doing before but then I read that when doing that the actual function doesn't get called but rather the result of the function ends up in that param position which isn't what I wanted. — terratunaz
– terratunaz, Commented Aug 11, 2016 at 22:04

Tomasz Jakub Rup · Accepted Answer · 2016-08-11 04:39:19Z

2

setTimeout run @checkProgress in window context. Use fat arrow:

setTimeout (() => @checkProgress), 5000

answered Aug 11, 2016 at 4:39

Tomasz Jakub Rup

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1 Comment

This worked, sort of. I ended up getting a different error. Undefined for the variables i was referencing in the method code.

terratunaz · Accepted Answer · 2016-08-11 22:02:44Z

0

This personally worked perfectly for me as well.

recall = =>
          @checkProgress()
        setTimeout recall, 5000

answered Aug 11, 2016 at 22:02

terratunaz

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