Writing to Info window swallowed by nocheck runScript used in assignment about praat HOT 4 OPEN

Further weirdness. It turns out that assigning the ID of a newly created object makes printing come back, but nothing gets printed if the ID is not assigned to anything. The following will work:

clearinfo
file$ = temporaryDirectory$ + "/temp.praat"
writeFileLine: file$,
  ... "a = Create TextGrid: 0, 1, ""Hello"", """""
appendFileLine: file$,
  ... "writeInfoLine: ""Hello"""
a = nocheck runScript: file$

But removing the ID assignment:

writeFileLine: file$,
  ... "Create TextGrid: 0, 1, ""Hello"", """""

makes the problem come back.

What is going on?

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What about this one:

clearinfo
file$ = temporaryDirectory$ + "/temp.praat"
writeFileLine: file$,
... "a = Create TextGrid: 0, 1, ""Hello"", """""
appendFileLine: file$,
... "writeInfoLine: ""Hello"""
b = nocheck runScript: file$
deleteFile(file$)
appendInfoLine: b

b will contain the unique id of the TextGrid...

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Or this:

a = nocheck writeInfoLine: 10
appendInfoLine: "<<", a, ">>"

This writes <<10>>, but without the nocheck it just writes <<1>>, which is the (meaningless) return value of writeInfoLine. Here you can see that using nocheck ignores the return value of the function (either runScript or writeInfoLine), so that the assignment only finds whatever was in the diverted info return buffer before. The return values of writeInfoLine and runScript are meaningless, so normally you would never see this interaction happen.

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The return value of writeInfoLine etc. are in general quite meaningless, because they always return 1. But they do so as far as they succeeded (or am I getting this wrong?). I actually do use the return value of runScript() in a procedure I wrote to try to implement a try ... catch style block. The idea being that you could write

include path/to/try.proc
call try
  ... # Next line has a typo            \n
  ... Crate TextGrid: 0, 1, "Hello", "" \n

if try.catch
  writeInfoLine: "There was an error"
endif

and not worry about whether or not your main script would fail (note how in that procedure I have to create an object as a placeholder, precisely to navigate around this problem, which back then was a lot more obscure to me).

I think the behaviour of nocheck is confusing. We've talked about this with regards to code like nocheck @procedure(), which did not do what I expected (disregard errors in the execution of that procedure) but instead skipped the procedure altogether.

And with the example you wrote, it seems nocheck also allows you to catch what is being written to the Info window?

What exactly does nocheck do? Or better yet: what do you consider to be the purpose of nocheck?

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