CodeCrafters
Build your own Interpreter
Learn about tokenization, ASTs, tree-walk interpreters and more.
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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.
Base Stages
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.
Parsing Expressions
This extension covers chapters 5 & 6 of the book (Representing Code & Parsing Expressions).
In this extension, you'll add the ability to parse expressions.
Evaluating Expressions
This extension covers chapters 7 of the book (Evaluating Expressions).
In this extension, you'll add the ability to evaluate expressions.
Statements & State
This extension covers chapters 8 of the book (Statements & State).
In this extension, you'll add the ability to add internal state to your interpreter & produce output.
Control Flow
This extension covers chapters 9 of the book (Control Flow).
In this extension, you'll add the ability to handle control flow statements like if/else, while & for.
Functions
This extension covers chapters 10 of the book (Functions).
In this extension, you'll add the ability to handle lox native functions & user-defined functions.
Resolving & Binding
This extension covers chapters 11 of the book (Resolving & Binding).
In this extension, you'll add the ability to semantically analyze variable declarations and resolve variable bindings at compile time.
Classes
This extension covers chapters 12 of the book (Classes).
In this extension, you'll add the ability to handle lox classes, instances, constructors and methods.
Inheritance
This extension covers chapters 13 of the book (Inheritance).
In this extension, you'll add the ability to handle class inheritance, method overriding and the super keyword.
Ananthalakshmi Sankar
Automation Engineer at Apple
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I think the instant feedback right there in the git push is really cool.
Didn't even know that was possible!
Patrick Burris
Senior Software Developer, CenturyLink