Overview of Differences & Highlights

A more detailed overview of the syntax can be found in the documentation.

• Whitespace sensitive blocks defined by indenting
• All variable declarations are local by default
• export keyword to declare global variables, import keyword to make local copies of values from a table
• Parentheses are optional for function calls, similar to Ruby
• Fat arrow, =>, can be used to create a function with a self argument
• @ can be prefixed in front of a name to refer to that name in self
• ! operator can be used to call a function with no arguments
• Implicit return on functions based on the type of last statement
• : is used to separate key and value in table literals instead of =
• Newlines can be used as table literal entry delimiters in addition to ,
• \ is used to call a method on an object instead of :
• +=, -=, /=, *=, %= operators
• != is an alias for ~=
• Table comprehensions, with convenient slicing and iterator syntax
• Lines can be decorated with for loops and if statements at the end of the line
• If statements can be used as expressions
• Class system with inheritance based on metatable’s __index property
• Constructor arguments can begin with @ to cause them to automatically be assigned to the object
• Magic super function which maps to super class method of same name in a class method
• with statement lets you access anonymous object with short syntax

Serious programming languages have alternative languages that compile.