debug.setupvalue

Replaces an upvalue captured by a closure.

Signature

debug.setupvalue(fn: function | number, index: number, value: any): ()

fnfunction | number

The closure to modify.

indexnumber

1-based upvalue index.

valueany

The replacement value.

Nothing.

luau

local counter = 10
local function read()
    return counter
end

debug.setupvalue(read, 1, 99)
print(read()) --> 99