SLFE

SLFE stands for Shitty LFE (LISP-flavoured Erlang).

It's a new programming language based on Elixir which aims to support all of the Enum functionality.

Overview

The big picture

The slfec compiler is a program that takes a foo.sl source file and produces a foo executable binary.

The isl REPL is an executable interactive program/environment (like Ruby's irb and Elixir's iex) for .sl programs.

These tools do not exist yet, but that's how you would ideally use SLFE.

To-do list

• Booleans
• UTF-8 Strings
• Integers
• Floats
• Multiple statements
• if expressions
• Equality checks with == and /=
• Functions
• Math operators (+, -, *, /)
• Linked lists

Code walk-through

This project is currently composed of 4 files:

Erlang

• src/lisp_lexer.xrl - Lexical analyzer generator
• src/lisp_parser.yrl - LALR-1 Parser Generator

Elixir

• lib/lisp_parser.ex - Layer on top of :lisp_lexer and :lisp_parser
• lib/lisp_evaluator.ex - Evaluates s-expressions and writes to stdio. Ideally the two things should be decoupled.

Running the test suite

You can do so by running mix test from the command line.

$ mix test
............................

Finished in 0.07 seconds
28 tests, 0 failures

FAQ

Should I use this?

Probably not. This is actually just an experiment, so I wouldn't recommend people using it to build actual programs. But feel free to use it anyway if you want.

Why Erlang/Elixir?

leex and yecc are the powerful Erlang alternatives to lex and yacc. I like Erlang, and Elixir is pretty rad too. So why not?

Is SLFE a Turing-complete language?

Yeah, I guess.

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SLFE was inspired by this blog post (thanks Andrea!).

Kudos to lpil for the name suggestion and for being awesome.