Hooking · Function

hookmetamethod

Hooks a specific metamethod on an object's metatable.

function hookmetamethod(objectobjecttable | userdataThe object whose metatable contains the metamethod to hook.: table, methodmethodstringThe metamethod name, e.g. "__namecall", "__index", "__newindex".: string, hookhookfunctionThe replacement function.: function): functionfunctionA trampoline to the original metamethod implementation.

Usage

Intercept __namecall on game

local origNamecall
origNamecall = hookmetamethod(game, "__namecall", function(self, ...)
  local method = getnamecallmethod()
  if method == "FireServer" then
    print("RemoteEvent fired:", ...)
  end
  return origNamecall(self, ...)
end)

Synopsis

Overview

Hooks a specific metamethodMetamethodA function in a metatable that overrides default behavior for operations like indexing (__index), assignment (__newindex), calling (__call), comparison (__eq), and arithmetic (__add, __mul, etc.). on an object's metatableMetatableA table attached to another table (or userdata) that defines operator overloading via metamethods (__index, __newindex, __call, etc.). Roblox Instances use shared read-only metatables for method dispatch., bypassing any __metatable lock. Typically used to hook __namecall, __index, or __newindex on Roblox Instances.

Shared metatable

All Roblox Instances share a single metatable. Hooking __namecall on any Instance. Even just game. Intercepts every :Method() call on every Instance in the game. Use getnamecallmethod() inside the hook and filter by self to target specific objects.

Common targets

__namecall. Intercepts :FireServer(), :FindFirstChild(), etc.
__index. Intercepts property reads like obj.Health
__newindex. Intercepts property writes
__tostring. Controls tostring(obj)