table.len

local length = table.len(input)

local t = {1, 2, 3, 4, 5}
local len = table.len(t)

engine.print("info", len) --5

local packed = table.pack(1, nil, 3, nil, 5)
local len = table.len(packed)

engine.print("info", len) --5

local t = {1, 2, nil, 4}
local len = table.len(t)

engine.print("info", len) --4 (may vary, depends on #)

local t = {}
local len = table.len(t)

engine.print("info", len) --0

local t = {1, 2, 3}

engine.print("info", table.len(t)) --3
engine.print("info", #t) --3

local args = table.pack("a", nil, "b", nil, "c")

engine.print("info", #args) --May be incorrect with nil holes
engine.print("info", table.len(args)) --5 (always correct)

local t = table.pack(1, nil, 2, nil, 3)

for i = 1, table.len(t) do
    engine.print("info", i, t[i])
end

local t = {}
if table.len(t) == 0 then
    engine.print("info", "Table is empty")
end

local t = {10, 20, 30, key = "value"}
local len = table.len(t)

engine.print("info", len) --3 (only counts array part)