WoW:API unpack

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WoW Lua

Returns the values in a consecutive-integer indexed table

ret1, ret2, ... retN = unpack(table[, start [, end]])

Will not return values with hash style indexes. For example:

local t = {1, "two", "3", x = "ecks", y = "why?"}
unpack(t) -- returns: 1, "two", "3"


(table) - A table
Integer - Starting index, defaults to 1 if nil
Integer - Ending index, appends nil values if the table does not contain enough


ret1, ret2, ... retN
A list of the values contained in the given table.


local arg1, arg2, arg3 = unpack({1, 5, "Hearthstone"})

-- This does the same thing:
local arg1, arg2, arg3 = 1, 5, "Hearthstone"
unpack({1,2,3,4,5},2,7)  -- returns 2, 3, 4, 5, nil, nil


unpack() doesn't return all the values in the following example because it is not a contiguous table.

 -- Notes Example 1
 t = {1,nil,"something",nil}
 print(unpack(t))  -- prints 1

A simple fix would be to add a value at the end of the list. This works because when you assign a table in this manner, Lua treats it as a contiguous table as long as there is a value at the last index. Nuking this value before adding new values at the end will break this behavior.

 -- Notes Example 2
 t = {1,nil,"something",nil,1}
 print(unpack(t))  -- prints 1 nil "something" nil 1
 t[5] = nil
 print(unpack(t))  -- prints 1

If you assign each value individually, unpack() will behave the same way it does in Notes Example 1.

 -- Notes Example 3
 t = {}
 t[1] = 1
 t[2] = nil
 t[3] = "something"
 t[4] = nil
 t[5] = 1
 print(unpack(t))  -- prints 1 even though it's the same contents as in Notes Example 2.