Lua datatypes

Primitives

Nil

• nil is the absence of a value
• nil within a table represents an absent key

nil

Boolean

true
false

Number

A single type number represents both 64-bit integers/floats.

123
123.4

String

An immutable byte-sequence, encoding-agnostic.
All strings must fit iwthin a single integer.

Function

Lua can call native lua, and C functions.

UserData

Represents a block of raw memory.
Passed as a reference.

• full userdata -- an object with a block of memory managed by lua
• light userdata -- a C pointer value

Thread

Passed as a reference.

Collections

Table

Associative arrays, passed as references to an object.

• keys any lua value, except nil (including functions)
• values may be any lua value, except nil