Passing something non-constant at compile time here is extremely dangerous, especially when users can replace those strings if they like.
It now uses FString::Substitute in all cases where something needs to be inserted into a template string.
This makes VMValue a real POD type with no hacky overloads and eliminates a lot of destructor code in all places that call a VM function. Due to the way this had to be handled, none of these destructors could be skipped because any value could have been a string.
This required some minor changes in functions that passed a temporary FString into the VM to ensure that the temporary object lives long enough to be handled. The code generator had already been changed to deal with this in a previous commit.
This is easily offset by the code savings and reduced maintenance needs elsewhere.
This reverts commit 76a44ebf9c.
Fix was done in the wrong place, it should be inside the script so that script-side calls to open a confirmation screen also get proper treatment.
The manager class cannot be scriptified because it provides the internal implementation which may change at some point in the future. It also encapsulates all access to the file level because if that part is not protected, modders could write malware mods.
This was done to ensure it can be properly overridden in scripts without causing problems when called during engine shutdown for the type and symbol objects the VM needs to work and to have the scripted version always run first.
Since the scripted OnDestroy method never calls the native version - the native one is run after the scripted one - this can be simply skipped over during shutdown.
Needless to say, this is simply too volatile and would require constant active maintenance, not to mention a huge amount of work up front to get going.
It also hid a nasty problem with the Destroy method. Due to the way the garbage collector works, Destroy cannot be exposed to scripts as-is. It may be called from scripts but it may not be overridden from scripts because the garbage collector can call this function after all data needed for calling a scripted override has already been destroyed because if that data is also being collected there is no guarantee that proper order of destruction is observed. So for now Destroy is just a normal native method to scripted classes
* everything related to scripting is now placed in a subdirectory 'scripting', which itself is separated into DECORATE, ZSCRIPT, the VM and code generation.
* a few items have been moved to different headers so that the DECORATE parser definitions can mostly be kept local. The only exception at the moment is the flags interface on which 3 source files depend.
