WoW:API select

Used to traverse a list. This function is usually used to capture the arguments passed to an ellipse (...). The official usage of this function is to return a list (retN) starting from index to the end of the list (list).

local ret1, ret2, retN = select(index, list)

Arguments

Parameters

index: Any non-zero number or the string "#".
list: Usually an ellipse (...).

Returns

retN: The number of items in the list or every value starting from index to the end of the list.

Examples

-- Common usage.
local num = select('#', ...) -- Returns the number of arguments in the ellipse.
local arg = select(i, ...) -- Returns the value at index i.

-- Print all of the function's arguments (those passed to the ellipse (...) only) to the default chat frame.
for i = 1, select('#', ...) do
    DEFAULT_CHAT_FRAME:AddMessage(select(i, ...))
end

local a, b, c = select(2, 'a', 'b', 'c')
-- a = 'b'
-- b = 'c'
-- c = nil

Notes

list can be value1, value2, value3, ... valueN; although, you will never see it used in that manner since you can just access value1 through valueN directly.
It is not recommended that you use this method on a table as you would have to pass the table to unpack() for every call to select (once plus the number of consecutive numeric indexes). For tables, use pairs() or ipairs().
Indexes beyond the number of list items will return nil.

select(6, 'see', 'dog', 'run') -- returns nil

An index of 0 will produce an "index out or range" error.
Negative values wrap to the end of the list.

select(-1, 1, 2, 3, 4, 5) -- returns 5

A decimal index will be rounded to the nearest integer (1.1 rounds to 1, 1.9 rounds to 2).

Disclaimer

Tested using the command line. Lua v5.1.2. Not tested in the WoW environment.

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