L4 Concepts

Understanding-oriented explanations of the principles, theories, and design decisions behind L4.

Purpose

Concepts documentation helps you understand:

Why L4 works the way it does
How different features relate to each other
When to use particular patterns or approaches
What theoretical foundations support L4's design

Unlike reference docs (which tell you what things are) or tutorials (which show you how to do things), concepts explain the why and provide deeper understanding.

Topics

🎨 Language Design

The philosophy and principles behind L4's design

Principles - Core design principles of L4

Key Ideas: Human-readable code, legal text fidelity, accessibility for non-programmers

More topics planned: Layout Sensitivity, Legal Isomorphism, Scope

⚖️ Legal Modeling

Representing legal concepts in code

Regulative Rules - Obligations, permissions, prohibitions

Key Ideas: Deontic modalities, legal rules as code, contract patterns

More topics planned: Deontic Logic, Contract Composition, Constitutive vs Regulative

🏗️ Type System

How L4's type system works

Algebraic Types - Sum types and product types

Key Ideas: Type safety, algebraic data types, functional programming influence

More topics planned: Maybe and Nothing, Type Inference

How to Use Concepts

During Learning

Read concept docs after you've tried the feature in practice
Concepts build on knowledge from courses and tutorials

For Deeper Understanding

Concepts explain the "why" behind language features
Use concepts to inform design decisions in your L4 programs

For Discussion

Concepts provide vocabulary for discussing L4 design
Reference concepts when proposing changes or new features