Lexical Structure

Identifiers

Identifiers in Elara have different semantic meaning based on the capitalisation of the first letter:

• Lowercase Identifiers identify terms, i.e. variables and function names. They must start with a lowercase letter (a-z) or an underscore (_) and can be followed by any combination of letters, digits (0-9), and underscores (_). Examples: myVariable, compute_sum, _temp123
• Uppercase Identifiers identify types and constructors. They must start with an uppercase letter (A-Z) and can be followed by any combination of letters, digits (0-9), and underscores (_). Examples: MyType, Option, TreeNode

Literals

Elara supports the following literal types:

• Integer Literals: A sequence of digits representing whole numbers. Examples: 0, 42, -123456
• Floating-Point Literals: A sequence of digits with a decimal point representing real numbers. Examples: 3.14, 0.001, -2.5
• String Literals: A sequence of characters enclosed in double quotes. Examples: "Hello, World!", "Elara is great!"
• Character Literals: A single character enclosed in single quotes. Examples: 'a', 'Z', '\n'

Keywords

The following are reserved keywords in Elara and cannot be used as identifiers:

• def
• let
• in
• type
• if
• then
• else
• match
• with
• module
• import
• class
• alias