hookmetamethod Synchronous
Replace a callable metamethod on an object and return its preceding implementation. An optional fifth argument filters calls before they reach the replacement.
Luau
hookmetamethod(
object: any,
name: string,
replacement: Function,
argguard: boolean?,
filter: HookFilter?
) -> FunctionParameters
| Parameter | Type | Description |
|---|---|---|
object | any | Object whose metatable contains the target metamethod. |
name | string | Metamethod name, such as "__call". |
replacement | Function | Function called when the filter matches. |
argguard | boolean? | Optional boolean. Defaults to true; false disables Kawaii’s minimum-argument guard for supported native userdata and vector C metamethods. |
filter | HookFilter? | Optional HookFilter in the fifth position. Pass nil for argguard when keeping its default. |
Returns
FunctionA callable for the preceding metamethod implementation.
Usage notes
ArgGuard does not apply to user tables and Luau metamethods. On supported native C metamethods it bypasses the replacement for calls missing required receiver, arguments, or namecall context; it does not type-check extra keys or method arguments.
A filter miss calls the preceding metamethod. Omit the filter or pass nil to handle every eligible call.
Example
Luau
local object = setmetatable({}, {
__call = function(_, value) return value * 2 end,
})
local original = getmetatable(object).__call
local previous
previous = hookmetamethod(object, "__call", function(self, value)
return previous(self, value) + 1
end, false, ArgumentFilter.new(2, 3))
print(object(3)) -- 7
print(object(4)) -- 8
restorefunction(original)