a)
TV_GetNext(ID, "Checked") and
TV_GetSelection() retrieve user input.
Bold, on the other hand, is always a direct result of the script, not the user, having set that state. It does not change after the item is added, unless the script changes it.
Perhaps
Bold indicates an item has some property that other items do not have, and you may want to later retrieve all such items. However, this only allows for a single binary property (absent or present, true or false), so I think it has very limited use. And because you know the item has the property when you add it, you can record that. For instance, if you assign
bold_items[n] := true or
bold_items.push(n) where
n is the node's ID, a simple for-loop will give you the bold items back. The same principle can apply to properties that can't be represented as TreeView item states.
b) I agree that "Bold0" should be supported, since "Check0" and "Expand0" are.
Commit ab077b61 fixes it.
Related comments from the source code:
//else since "de-select" is not a supported action, no need to support "-Select".
// Furthermore, since a TreeView is by its nature has only one item selected at a time, it seems
// unnecessary to support Select%VarContainingOneOrZero%. This is because it seems easier for a
// script to simply load the Tree then select the desired item afterward.
...
// Since this option much more typically used with TV_Modify than TV_Add, the technique of
// Vis%VarContainingOneOrZero% isn't supported, to reduce code size.
...
// Bold%VarContainingOneOrZero isn't supported because due to rarity. There might someday
// be a ternary operator to make such things easier anyway.
Wish 2) might also be valid for "Select|Vis|VisFirst" due to consistency.
To either perform the action or do nothing? It doesn't seem worthwhile to me.
