1. Implementation of a Functional Programming Language
Jason Koenig
Computer Systems Lab
TJHSST

2. Introduction Creation of a functional language
Both design and implementation
Working
Parsing
Simple Optimization
Execution
Ordered Evaluation
Todo: Optimizations

3. What is a Functional Language?
Two approaches:
Imperative – like a recipe, or a how to.
Declarative – like a mathematical formula.
Functions are first class citizens
Functions are like data

4. Design
Goals
Small and lightweight
Core language highly portable
Other functionality in standard library
Easily embedded in other programs as scripting language
Driven by implementation, rather than some external metric

5. Implementation File, Input Optimizer Executor Parser Program Output
Characters
Optimized Syntax Tree
Lexical
Analysis
Syntax Tree
Executor
Tokens
Characters
Parser
Program
Output

6. Sample Programs let x = 5, y = 6 in x+y # out: 11 let
in head.[x,y]
# out: 25

7. Future Work Recursion G-machine compilation Language
Tail Recursion
G-machine compilation
Language
Standard Library
Implementation: C for speed