How to create interpreter in go by Thorsten Ball

Main features

• C-like syntax
• variable bindings
• integers and booleans
• arithmetic expressions
• built-in functions
• first-class and higher-order functions
• closures
• a string data structure
• an array data structure
• a hash data struct

REPL

• the lexer
• the parser
• the Abstract Syntax Tree (AST)
• the internal object system
• the evaluato

The basic idea

Take a source code and parse then finally evaluate Source Code -> Tokens -> AST (Abstract Syntax Tree)

Creating tokens is done via the Lexer which is a functionality that analyzes the source code and tokenize its parts which are then fed to the AST

Here’s an example. This is the input one gives to a lexer:

"let x = 5 + 5;"

//And what comes out of the lexer looks kinda like this:

[
LET,
IDENTIFIER("x"),
EQUAL_SIGN,
INTEGER(5),
PLUS_SIGN,
INTEGER(5),
SEMICOLON
]