1. wdan_y
  2. meme

Overview

# About

meme is a minimal scheme. It's implemented in C, has GC, and should express reasonable TCO. Run the examples like so:

    $ ./meme fact.w
    5040


# Special forms

 (= a b)
    Evaluate `b` and store it in the current frame under the symbol `a`.
 (^ args... body)
    Captures the environment when invoked. Parameters are bound to the name of each `arg` in the evaluation of the `body` if called.
 (- a b...)
    The integers of `b` are each subtracted from the value of `a`.
 (< a b)
    `a` is numerically less than `b`.
 (? a b c)
    If `a` is not false, evaluate `b` else `c`.
 (# (a...) b)
    Returns a callable. Invoking it binds the arguments to each successive symbol in `a`. `b` is evaluated, and the returned expression is *again* evaluated, but this time in the macro callers environment.
 (* a...)
    Return the numerical product of all integers in `a`.
 (- a b...)
    If b is null, return `-a`

# Running under valgrind

Make sure to set G_SLICE=always-malloc, and possibly G_DEBUG=gc-friendly in the environment. See http://stackoverflow.com/questions/4254610/valgrind-reports-memory-possibly-lost-when-using-glib-data-types.

# TODO

 * Decide on the "nil" type. Void, empty, (), and others are all very similar. 
 * Use libreadline.
 * Use GMP for numbers.
 * Reintroduce tail call optimization.
 * Possible optimization: reclaim empty envs if they're only referenced by other environments.
 * Ditch hash tables in environments (except perhaps the top level one?)
 * Use slice allocator for pairs, and possibly other types
 * Cut back on unneeded loop detections.
 * Remove a lot of null checks by implementing "default" behaviours for all types.
 * Find out why slicing isn't as fast as raw malloc.