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add(t, v) -- add v to t
all(t) -- used in 'for v in all(t)' loops
count(t) -- returns number of elements in the table
del(t, v) -- delete first instance of v in t
foreach(t, f) -- call f() for each v in t
ipairs(t) -- loops through a numerically indexed table; for _, v in ipairs(t) do end
pairs(t) -- loops through string indexed tables; for k,v in pairs(t) do end
pack(...) -- adds any number of arguments into a table and returns the table
unpack(t) -- returns all entries in a table as arguments
rnd(t) -- returns a random value from a table

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mt = {} -- init metatable
setmetatable(t, mt) -- set metatable mt to table t

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-- object oriented programming; invoked as 't:foo()' / 't:bar()'
fun = {}
function fun.foo(t) dosomething() end
function fun.bar(t) dosomethingmore() end
mt.__index = fun
-- property assignment; invoked when calling 't[k] = v'
function mt.__newindex(t, k, v) rawset(t, k, v) end
-- weak references; keys and / or values
mt.__mode = "k" or "v" or "kv"
-- treat a table like a function; invoked when calling 't()'
function mt.__call(t) dosomething() end
-- hide metatable; returned by 'getmetatable(t)'
public_mt = {}
mt.__metatable = public_mt
-- string casting; returned by 'tostring(t)'
function mt.__tostring(t) return tostring(t) end
-- table length; returned by '#t'
function mt.__len(t) return #t end

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-- unary minus; returned by '-t'
function mt.__unm(t) return -t end
-- addition; returned by 'a + b'
function mt.__add(a, b) return a + b end
-- subtraction; returned by 'a - b'
function mt.__sub(a, b) return a - b end
-- multiplication; returned by 'a * b'
function mt.__mul(a, b) return a * b end
-- division; returned by 'a / b'
function mt.__div(a, b) return a / b end
-- modulo; returned by 'a % b'
function mt.__mod(a, b) return a % b end
-- involution; returned by 'a ^ b'
function mt.__pow(a, b) return a ^ b end
-- concatenation; returned by 'a .. b'
function mt.__concat(a, b) return a .. b end

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-- check for equality; returned by 'a == b'
function mt.__eq(a, b) return a == b end
-- check for less-than; returned by 'a < b'
function mt.__lt(a, b) return a < b end
-- check for less-than-or-equal; returned by 'a <= b'
function mt.__le(a, b) return a <= b end