PL Theory

1. Overview

Programming Language Theory (PL Theory): The study of formal languages, their structure, and their computational properties.
Key Concepts:
- Syntax: The rules that define the structure of valid statements in a programming language.
- Semantics: The meaning associated with the syntactic constructs; how programs behave.
- Pragmatics: The context-dependent aspects of language use; user interaction and system behavior.
Type Systems:
- Static vs. Dynamic Typing: Static typing checks types at compile time; dynamic typing checks at runtime.
- Strong vs. Weak Typing: Strong typing prevents operations on mismatched types; weak typing allows more flexibility.
Language Paradigms:
- Imperative: Focuses on commands and state changes (e.g., C, Java).
- Functional: Emphasizes functions and immutability (e.g., Haskell, Lisp).
- Object-oriented: Uses objects and classes (e.g., Python, Ruby).
- Logic-based: Employs formal logic to express computations (e.g., Prolog).
Formal Methods: Techniques for specifying and verifying properties of programs, ensuring correctness.