Feature request: Provide warning before discarding changes

[riban-bw]

When an new instrument is selected or the application is closed, there is no check for changes of the existing instrument. It would be advantageous to provide a warning that changes will be lost and offer to save changes. A dialog with three options may be appropriate:

• Save: Save the existing instrument then continue with the requested operation.
• Cancel: Cancel the requested operation.
• Discard changes: Do not save changes and continue with the requested operation.

This may be useful for the following operations:

• Open instrument
• Close application

[owingsbj]

I'm wondering if this should really be done. I decided on the current behavior because it is similar to most other hardware and software synthesizers, which also do not prompt to save when switching instruments. I could add the prompt only in the case where the module graph was edited. Let me know if that seems acceptable to you.

[riban-bw]

In performance mode a user would want to adjust parameters without saving to the patch, e.g. sweeping a filter manually. During patch editing the user wants to decide whether to save changes or discard them. Some synths use an edit buffer where the changes are temporarily stored and may be recalled even if a different patch has been selected but I don't think that helps here. One solution might be to implement a performance mode (which may have other uses) which does not request confirmation for patch change. It is a more complex implementation but I have reported other issues / feature requests which may benefit from a performance mode. What do you think?
It may also be worth clearly indicating that a patch has changed so that a user is more aware they are about to overwrite changes. This could be changing the colour of an area of screen, marking the patch name with a character, e.g. "*" and / or changing the colour of the patch selection dialog.