Note that this completely disables the newly added keywords 'play' and 'ui' for unversioned code to allow using them as identifiers as I have found at least one mod that uses a variable named 'play' that would have been rendered broken otherwise.
This also disables many ZScript only keywords for other parsing jobs.
- support transient object member variables for information that does not need to be put in a savegame.
- fixed: special initialization of objects needs to pass the proper defaults along, otherwise the parent classes will use their own, inappropriate one.
* It will now use #include, just like most other definition formats and can be mixed with regular definitions. However, due to how the Lemon-generated parser works this will not recursively pull in all files, but store them in a list and process them sequentially. Functionally this shouldn't make a difference, because ZScript is mostly order-independent - the only thing where order is important is native classes, but these are completely internal to zdoom.pk3 where proper order is observed.
- added new VM instructions to access the constant tables with a variable index.
- refactored VMFunctionBuilder's constant tables so that they are not limited to one entry per value. While this works fine for single values, it makes it impossible to store constant arrays in here.
- implemented multiple-return-value assignment. Due to some grammar conflicts the originally intended Lua-inspired syntax of 'a, b = Function()' could not be done, so it's '[a, b] = Function()'
- added a new type 'NativeStruct'. This will be used for types that cannot be instantiated, and is also needed to cleanly handle many internal types that only can exist as reference.
Syntax-wise I chose to make it as strict as possible to reduce the chance of errors: Virtual base functions must be declared with the 'virtual' keyword, and overrides in child classes with the 'override' keyword. This way any mismatch in parameters that otherwise would cause silent failure will outright produce a compile error.
- added initializer syntax for vectors. A vector can be set with vectorvar = (x,y,z); for a 3-dimensional vector and vectorvar = (x, y); for a 2-dimensional one.
- removed 'self' as a dedicated token. Internally this gets handled as a normal but implicitly named variable so the token just gets in the way of proper processing.
- removed P_ prefix from SpawnMissile export.
- fixed a crash with misnamed function exports.
- allow class extensions.
These are separate blocks in different files that get concatenated to one class body for processing. The reason is to allow spreading the many functions in Actor over multiple files, so that they remain manageable. For example, all the Doom action functions should be in their respective files, but their symbols need to be in Actor. To extend a class, both files need to be in the same translation unit, so it won't allow user-side extension of internal classes.
- fixed: FxMemberIdentifier checked for ClassPointers instead of object pointers to resolve the left hand side of the expression.
- allow comparison of pointers.
This also means that for now Lua-style multi-assignments are disabled, those should be easy to enable by making some changes to the assignment_statement grammar so that it doesn't recognize single assignments, but for now this is low priority because it adds a significant amount of complexity to do this right with functions that have multiple return values.
- added the '>>>' (unsigned shift) operator. Although, with unsigned numbers available, this is technically not really needed, DECORATE supports this so ZScript should, too, if only for the benefit of making conversion tools easier to handle.
These were previously faked with the inverse plus a boolean not. Although this works, it either leads to sub-optimal code generation or some fudging to avoid the inefficient handling.
Just adding proper handling to the parser seems the easiest and most straightforward way to get around this. The code generator already can deal with these operations properly so there's no good reason to do it differently.
- use FScriptPosition's error counter throughout the compiler so that there is only one counter for everything, not two.
Parts of the compiler use FScriptPosition, so this is easier to handle than having a separate counter in the compiler class. It also avoids having to pass the compiler object to any function where an error may be output. The TreeNodes contain sufficient data to be converted to an FScriptPosition and using that for error message formatting.
- fixed a few problems that were encountered during conversion:
* action specials as action functions were not recognized by the parser.
* Player.StartItem could not be parsed.
* disabled the naming hack for PowerupType. ZScript, unlike DECORATE will never prepend 'Power' to the power's name, it always needs to specified by its full name.
* states and defaults were not checked for empty bodies.
* the scope qualifier for goto labels was not properly converted to a string, because it is an ENamedName, not an FName.
