Digamma: my attempt at “Lisp for the 21st Century”

DIGAMMA TODO

Current Vesta Stable Release: 6.7-alpha

Current Vesta WIP release: none

Current Hydra release: 0.1-alpha

Digamma is a dialect of scheme that provides several advanced features:

Dictionary literals in a ruby/python style: {:test 1 :dictionary 2}
Quoted vector literals using [ ]
Dictionaries are backed by tries, and keys can be queried as to matches or length match
Applicable data structures
Levels of specification, to allow Digamma to be implemented everywhere
A PreScheme-like restricted dialect that allows for Systems-level programming
W7-like environments for safe code evalution in programmatically created environments
A Collection API (first,rest,cset!,nth,cupdate) that applies a purely-functional style to all collections (lists, dicts, vectors, strings)
Various interfaces to lambdas: case-based (CaML/Haskell-style), Keyword (Python/extended SRFI-89 style), CL (with :rest, :opt, :body, &c.) & standard.
Strong specificty of POSIX interactions, to avoid the normally academic feel of Scheme dialects.
a “batteries included” approach to library inclusion, with a focus on real-world requirements (SMTP, HTTP, IMAP, Pop3, pentration testing, &c.
Work in Progress: types ala Stalin

It comes in a few flavors:

Vesta: the reference implementation written in C
Hydra: the work in progress, which is meant to replace Vesta eventually, and self-hosts. Compiles Digamma to a SECD-like VM.
Enyalios: a “Pre-Digamma” compiler (restricted subset) which is meant to be a better compilation framework than E’ (Eprime)
Eprime/E’: the initial Digamma -> Compiler, which was shelved because working on it was painful. Enyalios is a complete rewrite and meant to be extensible.
Nyx/Aneris: simple test interpreters to try out self-hosting interpreters, but are AST walkers.
Ceres: a register-VM that was shelved (then started again, then shelved…).

6.7-alpha: fixes, consistency, &c.
6.6-theta: efficiency tuning of TCO, W7 & define-syntax overhaul
6.6-eta: true TCO, help, docstrings
6.6-zeta: testing release
6.6-delta: major re-organization of internals, many, many bug fixes
6.6-gamma: prelude/init.ss work, internals, better display from FORMAT
6.6-beta: over-haul of collexions (tries, tconcs, cslice), removal of certain primitives that could be implemented in higher-level forms (like cond) and switch of internal Environment storage format (mixture of Linked lists & tries)
6.6-alpha: switched from lleval (old, recursive style) to _seval (stackless version), and removed debugging
6.5-gamma: added _seval (stackless) and switched primitives to use this stack
6.5-beta: start of stackless system, bug fixes to lleval
6.5-alpha: changes to closure application
6.4: aborted attempt at better internal organization (aborted because it became very messy; premature optimization root of all evil :D)
6.3: bug fixes, multiple changes
6.2: stablized read system
<= 6.1: ancient stuff

0.1-beta: cleaned up instruction set a bit, to reduce number of instructions needed.
0.1-alpha: finalized the basic instruction set.
0.0-gamma: continuations working nicely.
0.0-beta: fixed accidental scope breakage.
0.0-alpha: basic proof-of-concept fork from Nyx/Aneris.