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Build your own Interpreter

Learn about tokenization, ASTs, tree-walk interpreters and more.

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Build your own Interpreter

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This challenge follows the book Crafting Interpreters by Robert Nystrom.

In this challenge you'll build an interpreter for Lox, a simple scripting language. Along the way, you'll learn about tokenization, ASTs, tree-walk interpreters and more.

Before starting this challenge, make sure you've read the "Welcome" part of the book that contains these chapters:

Introduction (chapter 1)
A Map of the Territory (chapter 2)
The Lox Language (chapter 3)

These chapters don't involve writing code, so they won't be covered in this challenge. This challenge will start from chapter 4, Scanning.

Stages

Scanning: Empty file

Scanning: Parentheses

Scanning: Braces

Scanning: Other single-character tokens

Scanning: Lexical errors

Scanning: Assignment & equality Operators

Scanning: Negation & inequality operators

Scanning: Relational operators

Scanning: Division operator & comments

Scanning: Whitespace

Scanning: Multi-line errors

Scanning: String literals

Scanning: Number literals

Scanning: Identifiers

Scanning: Reserved words

Parsing Expressions

Number literals

String literals

Unary Operators

Arithmetic operators (1/2)

Arithmetic operators (2/2)

Comparison operators

Equality operators

Syntactic errors

Evaluating Expressions

Literals: Booleans & Nil

Literals: Strings & Numbers

Unary Operators: Negation & Not

Arithmetic Operators (1/2)

Arithmetic Operators (2/2)

String Concatenation

Relational Operators

Equality Operators

Runtime Errors: Unary Operators

Runtime Errors: Binary Operators (1/2)

Runtime Errors: Binary Operators (2/2)

Runtime Errors: Relational Operators

Statements & State

Print: Generate output

Print: Multiple statements

Expression statements

Variables: Declare variables

Variables: Runtime Errors

Variables: Initialize variables

Variables: Redeclare variables

Assignment operation

Control Flow

Else statements

Else-if statements

Nested if statements

Logical OR operator

Logical AND operator

While statements

Syntactic errors

Functions

Native functions

Functions without arguments

Functions with arguments

Return statements

Higher order functions

Resolving & Binding

Identifier Resolution

Self Initialization

Variable Redeclaration

Classes

Class Declarations

Class Instances

Getters & Setters

Instance Methods

The 'this' keyword

Invalid usages of 'this'

Constructor calls

Return within constructors

Inheritance

Class Hierarchy

Inheriting Methods

Overriding Methods

Inheritance errrors

The super keyword

Invalid Usages of the super Keyword

RECENT ATTEMPTS 0

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Patrick Burris Senior Software Developer, CenturyLink