How to get 'self' from Lua event handler function?

Question

local tbl = {a = 1}

-- Passed and executed function
function tbl:handleFunc(x, y)
    print(self.a + x + y)
end

-- I know the above code is syntax sugar.
-- tbl["handleFunc"] = function(self, x, y)
--     print(self.a + x + y)
-- end

-- Register event handlers that I can't control the call
Frame:SetScript("OnClick", tbl.handleFunc)

-- Probably called when an event occurs.
tbl.handleFunc(2, 3)

-- Then it will be like this.
tbl.handleFunc(2, 3, nil)

-- So I wrote a function like this
function tbl.handleFunc(x, y)
    local self = tbl  -- This variable is too cumbersome
    -- And this way, every time I call a function, I need to check whether the function definition is a dot (.) Or colon (:)

end

When calling a function, In situations where you can't pass self, Is there a way to use self?

If not, how should I design?

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[Solved] I used a translator but I want to be polite. Thank you for the nice answers.

Answer 1

One way to avoid unnecessary work is to write a function that will wrap the function for you before you register it as a handler:

local tbl = {a = 1}

function tbl:handleFunc(x, y)
    print(self.a + x + y)
end

function wrap_with(obj, func)
    return function(...)
        return func(obj, ...)
    end
end

Frame:SetScript("OnClick", wrap_with(tbl, tbl.handleFunc))