[texworks] SCRIPTING: Happy New Year to ALL! - openFileFromScript

[Stefan Löffler]

On 2011-01-01 06:41, Paul A Norman wrote:
> Happy New Year to ALL!

Yeah, happy new year! Hopefully, we'll see a Tw release this year :P.

> Can't yet test openFileFromScript() (thanks for putting that in Stefan)
>
> Debugger says ...
>
> "Uncaught exception at
> D:/LaTeXPortable/LatexUtils/TeXworks/TeXworks/config/scripts/Scripting
> - Experiments/tw_OBJECT.js:19: TypeError: cannot call
> openFileFromScript(): argument 2 has unknown type `TWScriptAPI*'
> (register the type with qScriptRegisterMetaType())
> 19	var   ret =  TW.app.openFileFromScript('c:/hold/MyFile.txt', null,
> -1, true);"
>
> Tried second argument with various, however can see that it is
> complaining that something is not set/registered in Scripting engine?
> Would this argument effectively disappear from User's scope if already
> registered? and then the following be renumbered back one?

No. You should pass TW to that parameter. The reason for this is that in
the TW.app context, we have no direct access to the calling script, and
therefore can't perform any security checks. For that we need TW (or,
more precisely, TW.script, at the moment; but because this prerequisite
might change in the future, we stick to TW for the moment).
So you should put something like this in your script:
var ret =  TW.app.openFileFromScript('c:/hold/MyFile.txt', TW, -1, true);

I tested (something like) this, and it worked for me.

You are right, though, that passing null shouldn't crash the script. So
I modified the code in r727 so that arbitrary objects can be passed (but
only TW makes sense).



> 3rd argument desired cursor position?

Yes

> 4th argument whether to prompt user if file read permission not set to
> True in Preferences?

Yes. More generally, this flag determines if the user should be asked if
the file should be opened if read permissions are insufficient, or if
the function should just fail silently without bothering the user (the
default). The idea behind this is twofold:
 * You'll often want to open a single file for the user to inspect
(otherwise you could just use readFile). In this case, there is no
reason to force the user to enable global reading, but instead we give
him the chance to decide on a per-file basis if he wants to grant access
to that file to the script. For this, set the askUser flag to true.
 * If, for some reason, you want to open a (larger) number of (related)
files, you don't want to bother the user each time asking for
permission. Instead, the function should fail silently, the script
should catch that, and terminate with a message telling the user how to
enable global reading. So by default, this function behaves exactly like
readFile.

HTH
Stefan