Compilers, Interpreters & Formal Languages

Source: https://pikuma.com/courses/create-a-programming-language-compiler

This course is designed to be a beginner-friendly introduction to compilers. As we evolve, we will incrementally put together an interpreter for a very simple scripting language.

We’ll cover:

Lexical analysis
Syntax analysis
Parsing algorithms
Intermediate representation (AST)
Formal languages & grammars
BNF notation & syntax diagrams
Identifying and reporting errors
Code generation
Writing our own VM
Emitting opcodes and instructions
Type checking
…and much, much more!

Compilers always had a reputation for being a difficult topic, and their historical association with dragons 🐉 (starting with the Dragon Book) never really help the cause. make your own programming language

We’ll try to approach every explanations with beginners in mind. You can think of it as a “first course” on compilers for developers that never wrote an interpreter before. What we’ll build

We’ll build together, from the ground up, a compiler for a simple programming language called Pinky. Think of a toy scripting language with a syntax inspired by Lua and ALGOL W.

x := 0
pi := 3.141592
name := 'Pinky'

-------------------------------------
-- Find the max between two numbers
-------------------------------------
func max(a, b)
  if a > b then
    ret a
  end
  ret b
end

-------------------------------------
-- Compute the factorial of a number
-------------------------------------
func factorial(n)
  if n == 1 then
    ret 1
  else
    ret n * factorial(n - 1)
  end
end

-------------------------------------
-- Main function
-------------------------------------
func main()
  i := 0
  while i <= 10 do
    print(i)  
    i := i + 1
  end
  for i := 1, 10 do
    print(factorial(i))
  end
end

main()

Our main host language will be Python. Python allows us to focus our attention on compiler-specific concepts while being extremely productive. Still, I’ll try to include some helpful tips on how to implement the ideas we just learned using the C programming language.