Lua Module support
Starting in FTSE 0.60a, Lua modules are now fully supported. This allows independent units of functionality to be developed with minimal conflict. Modules can implement their own version of each hook function (including Entity vtable hooks).
Installing a hook within a module
To install an instance of a regular hook from within a module, it is best to use a local function (or, if the function must be global, use a name different than the normal hook function name). Then, use the hookexecutor:InstallHook function to register the hook.
To install an entity vtable hook, use the same hookexecutor:InstallVtableHook function that is normally used.
Hooks are executed in the order they are defined, with the global function being called last. If a module depends on being called in a specific order, the order of the module "require" statements should reflect the desired order that hook functions are called.
Returning from a hook
Since multiple hook functions can potentially be called for the same event, the return value for each function is important:
For a regular hook function with no return value: Each hook should normally return with no value. This will allow the next defined hook for the event to run. If a hook wants to prevent later defined hooks from running (e.g. the hook fully implements the behavior of the event), then it can return the value NO_CHAIN.
For a regular hook function with a return value: Each hook function should determine if the event should be handled by that module, or left for the next module. If the hook function is to process the event, then the appropriate value should be returned. Otherwise, an empty return can be used to let the next hook function (if any) handle the event.
For an entity vtable hook function: The same considerations apply for functions with expected return and no return. An additional consideration is the original vtable function. If the last hook executed issues an empty return, then the original vtable function will automatically be called (this behavior differs from 0.56a). So in most cases, explicitly calling the Entity:CallOrigVtable function will not be necessary. A hook can still prevent the original vtable function from being called by either returning a valid return value, or NO_CHAIN.