Summary

• What is Lean
• Tour of Lean
• Setting Up Lean
  • Extended Setup Notes
• Theorem Proving in Lean
• Functional Programming in Lean
• Examples
  • Palindromes
  • Binary Search Trees
  • A Certified Type Checker
  • The Well-Typed Interpreter
  • Dependent de Bruijn Indices
  • Parametric Higher-Order Abstract Syntax

Language Manual

• Organizational features
  • Sections
  • Namespaces
  • Implicit Arguments
  • Auto Bound Implicit Arguments

• Syntax Extensions
  • The do Notation
  • String Interpolation
  • User-Defined Notation
  • Macro Overview
  • Elaborators
  • Examples
    • Balanced Parentheses
    • Arithmetic DSL
• Declaring New Types
  • Enumerated Types
  • Inductive Types
  • Structures
  • Type classes
  • Unification Hints
• Builtin Types
  • Natural number
  • Integer
  • Fixed precision unsigned integer
  • Float
  • Array
  • List
  • Character
  • String
  • Option
  • Thunk
  • Task and Thread
• Functions
• Monads
  • Functor
  • Applicative
  • Monad
  • Reader
  • State
  • Except
  • Transformers
  • Laws

Other

• Frequently Asked Questions
• Significant Changes from Lean 3
• Syntax Highlighting Lean in LaTeX
• User Widgets
• Semantic Highlighting

Development

• Development Guide
• Building Lean
  • Ubuntu Setup
  • macOS Setup
  • Windows MSYS2 Setup
  • Windows with WSL
• Bootstrapping
• Testing
• Debugging
• Commit Convention
• Release checklist
• Building This Manual
• Foreign Function Interface