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Suppose I got in a Dialog and wanted to not Return but Abort the computation. How could I do that?

Using Return[] the computation continues, and sometimes that implies getting inside countless other Dialogs of which it is not easy to go out without killing the kernel.

How do you handle those situations?

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I use ExitDialog@Unevaluated@Abort[]

If your dialog is unhappily inside a CheckAbort you can go for exceptions like ExitDialog@Unevaluated@Throw["OOOUT", Unique[]] for example.

In this way, tools like TraceDialog become very useful. TraceDialog[code, Message] is something I use often, to see the Stack, the state, etc

Note that this only aborts one level. If you want 2 levels you could do ExitDialog@Unevaluated@ExitDialog@Unevaluated@Abort[]

For a general way to abort all dialogs of any level at once, one could do

Apply[Composition,
  ConstantArray[Function[i, ExitDialog@Unevaluated@i, HoldFirst], 
   DialogLevel[]]][Unevaluated@Abort[]]
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  • $\begingroup$ Seems that ExitDialog is equivalent to Return in this case? $\endgroup$ – xzczd Jan 18 '17 at 4:53
  • $\begingroup$ @xzczd in what case? $\endgroup$ – Rojo Jan 19 '17 at 1:59
  • $\begingroup$ I mean ExitDialog@Unevaluated@Abort[] and Return@Unevaluated@Abort[] has the same effect? $\endgroup$ – xzczd Jan 19 '17 at 5:58
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    $\begingroup$ @xzczd That didn't work for me last I tried. It made the dialog return Unevaluated@Abort[] so nothing got aborted. $\endgroup$ – Rojo Jan 20 '17 at 6:08
  • $\begingroup$ @xzczd yeah. It seems Return returns even when run without [...], and the Unevaluated doesn't work as one would expect. $\endgroup$ – Rojo Jan 20 '17 at 6:12

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