Files
playdate-kit/Sources/PlaydateKit/Lua/Structures/UDObject.swift
T

33 lines
1.1 KiB
Swift

internal import CPlaydate
extension Lua {
/// A handle to a Lua-owned object. Wraps `LuaUDObject`.
public struct UDObject {
let pointer: OpaquePointer
/// Prevents the object from being garbage-collected until `release()`.
@discardableResult
public func retain() -> UDObject {
UDObject(pointer: luaAPI.pointee.retainObject.unsafelyUnwrapped(pointer).unsafelyUnwrapped)
}
public func release() {
luaAPI.pointee.releaseObject.unsafelyUnwrapped(pointer)
}
/// Pops the value on top of the stack and stores it in the object's
/// user-value `slot` (1-based).
public func setUserValue(slot: UInt32) {
luaAPI.pointee.setUserValue.unsafelyUnwrapped(pointer, slot)
}
/// Pushes the value in user-value `slot` onto the stack and returns
/// its stack position, or `nil` if there is none.
@discardableResult
public func getUserValue(slot: UInt32) -> Int? {
let position = luaAPI.pointee.getUserValue.unsafelyUnwrapped(pointer, slot)
return position == 0 ? nil : Int(position)
}
}
}