15312 Foundations Of Programming Languages ❲2025❳

This essay outlines the core philosophy and technical pillars of 15-312: Foundations of Programming Languages, a course famously centered on the rigorous study of language design through the lens of type theory and operational semantics.

1. Provide additional resources: Offering supplementary resources, such as textbooks, online tutorials, or study groups, can help students better understand the course material.
2. Increase feedback opportunities: Providing more frequent and detailed feedback on assignments and exams can help students identify areas for improvement and track their progress.
3. Encourage student participation: Encouraging student participation in class discussions and providing opportunities for students to engage with the material can enhance the learning experience.

• Shared memory (with mutexes) – easy to get wrong (deadlock, race conditions).
• Message passing (Erlang, Go) – more disciplined, but still complex.
• Software Transactional Memory (STM) – like database transactions for memory.

Example study plan (6 weeks, assuming background in PL)

Week 1: Lambda calculus, ASTs, evaluation rules, write an interpreter.
Week 2: Simply typed lambda calculus, typing rules, implement type checker.
Week 3: Hindley–Milner basics, unification, start implementing Algorithm W.
Week 4: Progress & preservation proofs for core language.
Week 5: Polymorphism/System F overview, CPS conversion.
Week 6: Effects and moduless, final project polishing and write-up. 15312 foundations of programming languages

In this example, the identity function takes an argument x and returns it unchanged. Our type inference algorithm infers that identity has a type scheme forall a. a -> a, indicating that it works with any type a. This essay outlines the core philosophy and technical

15-312: Foundations of Programming Languages (FPL) at Carnegie Mellon University is more than just a coding course; it is a deep dive into the mathematical soul of software. While many computer science courses focus on to use a language, 15-312 asks a more fundamental question: Shared memory (with mutexes) – easy to get

Standard ML (SML): The primary implementation language is SML, which students use to build interpreters for various language models directly from their formal definitions. Key Topics Covered

-- Type.hs
data Type = TV String | TCon String [Type] deriving (Show, Eq)