Library "Catch errors in a script" terminates calling script when used in a reporter.

[dlnelson]

When using "safely try . . ." in a reporter, when an error occurs, the error handler runs, but the calling script terminates. I've attached the smallest repro I could find:

ErrorHandlingTest.zip

Note that running <should report true> at top level displays a report bubble with <true>, but using it in, e.g., an if-statement fails.

Rewriting using a continuation seems to work, but isn't really a solution suitable for beginners:

[brianharvey]

This works:

The trouble is that the RETURN block in the error handler is returning from the wrong context, I think. Jens is going to tell me that this is what I get for letting 12-year-olds write libraries...

[jguille2]

But the problem here is to mix synchronous and asynchronous actions. I can not build a sync stack with async call inside... I need to call the async action before and send the sync action as a callback.

Let's see:

• We can define this predicate:
  
• It seems to be fine
  
• But it isn't!
  
• Then, we need to define the checking as an action (not a reporter-predicate)
  
• See that these actions have the same result
  
• But be careful! This also has the same result!!
  

We can reproduce more problems using async "safely try" into reporters-predicate blocks definition. We must change these cases to actions blocks. Or we must change "safely try" block to a sync operation.

[Naharie]

Can anyone tell me what corner cases I am missing? I made a change that makes all the test cases work. Here is the updated project:
ErrorHandlingTest.zip

[jguille2]

Oh @KingDavid12 ,
But you have changed 'safely try' block!!!! 👿

Original block (from distro):

And your modification...

Apart from discussing how the blog should be (could be another issue), I think the current behavior and this issue (the project reported) is only a question about sync-async operation.

Joan

[Naharie]

@jguille2 Sorry about that, I misunderstood what the focus of the thread was about on my first read through.

[brianharvey]

I'm confused... @jguille2: If @KingDavid12's modified SAFELY TRY works in all cases, shouldn't we replace the library one with that?

[Naharie]

@brianharvey I don't know that it will work in all existing projects, I only tried my modified one on the examples in the thread and a few projects of my own. (Beside the point: Is there an official set of tests for this kind of thing?) So we should probably run a few more test cases before just using it.

[jguille2]

Don't worry @KingDavid12 (I joked after being freaking without knowing why the block suddenly had a different behavior 😄 ... and I like your comments and examples in Snap! )

@brianharvey I have no criteria to comment here about SAFELY TRY modifications. I just commented to help into @dlnelson issue and to show the workaround according to current behavior. Certainly current code is more complex than @KingDavid12 ones, but I don't know exactly the aims of the lib block.