Juergen Lorenz
ju (at) jugilo (dot) de
I am a mathematician and a member of the "small is beautiful" crowd. And R5RS-Scheme is the definite example, that a small language is possible which allows one to do almost everything with it. And that in a clear syntax -- or should I better say -- with almost no syntax at all? And it is a programmable programming language! You can always add new syntax to it.
In my mind, Chicken is the best Scheme implementation. Its compiler compiles to C in the most ingenious way, it has the simplest interface to C, and it has a beautiful infrastructure, the eggs system, a helpful community and, and, and ...
Chicken 5 Eggs
anaphora
some anaphoric macros, some of them accompanied by equivalent named ones.
arrays
An implementation of functional arrays (of variable length) and - as an application - of sets.
biglists
an attempt to unify access to lists and lazy-lists, either finite or infinite.
bindings
A light-weight alternative to the matchable egg, with many enhancements.
A number of binding macros is provided, which can destructure pseudolists and arbitrary mixtures of pseudolists, vectors and strings, as well as other sequence types, the client may add later. The most important one is bind, a variant of Common Lisp's destructuring-bind.
callable-sequences
a common extendable functional interface to various flat and nested sequence types, including lists, pseudolists, vectors and strings.
checks
Procedures and macros that help to check pre- and postconditions
continuations
some additional interfaces to continuations
dotted-lambdas
a version of lambda, called lambda*, which accepts lists terminating with two, three or four dots referencing a list to its left of at most one, arbitrary many or at least one item respectively.
generics
an implementation of generic functions
holes
Transform expressions with holes into procedures with the holes as argument names. Here, a hole is symbol, consisting of zero or more digits enclosed in < and >.
iterators
a simple implementation of iterators and coroutines.
list-comprehensions
Some list creating procedures, in particular a variant of Clojure's for macro
locals
Three simple macros inspired by ML's local definitions
messages
An implementation of algebraic-types and abstract-types, based on messages, which are (functional) vectors tagged with a type keyword and a variant keyword.
pipes
piping partial combinations from left to right
premodules
creating a module-file, a tests-file and documentation automatically from one premodule file.
procedural-macros
Some macros to facilitate the writing of procedural macros, including define-macro and macro-rules, which mimics syntax-rules. All destructure the macro-code automatically behind the scene, using macros from the bindings egg. Renaming is simplified as well.
pseudolists
Routines to handle pseudolists as a generalisation of lists.
simple-cells
Another simple implementation of the cell datatype, a lightweight variant of boxes.
simple-contracts
design by contract for procedures.
simple-exceptions
An easy to use exception wrapper around chicken's condition system.
simple-loops
some simple loop macros.
simple-sequences
common extensible interface to various sequence types, in particular lists, pairs, vectors, strings
simple-tests
Some simple macros and commands which help debugging and testing.
skiplists
an implementation of skiplists
tree-walkers
replacement of the nested car and cdr routines
Chicken 4 Eggs
These eggs will no longer be maintained. Most of them are ported to Chicken 5.
basic-macros
Some macros which help to write procedural macros. For example, define-er-macro does the renaming and bind the destructuring automatically. bind and bind-case are simplyfied versions of the equally named macros in the bindings egg, which are sufficient for macro-writing.
procedural-macros
Some macros which help to write procedural macros. For example, a hygienic version of define-macro and a procedural variant of syntax-rules, called macro-rules, which is as easy to use as the latter but much more powerfull.
bindings
A light-weight alternative to the matchable egg, with many enhancements.
A number of binding macros is provided, which can destructure arbitrary mixtures of lists, pseudolists, vectors and strings, as well as arbitrary sequence types, the client may add later. The most important one is bind, a variant of Common Lisp's destructuring-bind.
datatypes
An implementation of concrete and abstract types, the former beeing discriminated variant records, as advocated by Friedman, Wand and Haynes in "Essentials of programming languages" and ported to Chicken by Felix Winkelmann. The latter are based on the former, but hide the variant constructors and export constructor and accessor procedures instead. A simple object system is also provided.
locals
Implementation of a local macro inspired by the equally named operation in ML.
holes
Transform expressions with holes into procedures with the holes as argument names. Here, a hole is symbol, consisting of zero or more digits enclosed in bangs.
list-comprehensions
Some list creating procedures, in particular for and for*
anaphora
Anaphoric macros, which are unhygienic by design. Most of them insert the special identifier "it" behind the scene.
loops
Some simple loop macros.
tuples
Something like immutable random-access vectors, with empty, couples and triples as special cases, and mutable singles as a possible replacement of boxes.
simple-cells
Another simple implementation of the cell datatype, a lightweight variant of boxes.
typed-lists
a functor implementation of typed and immutable lists and sets.
arrays
An implementation of functional arrays and - as an application - of sets.
basic-sequences
basic sequence-routines, which are used in bindings and can be used for a full-flegded sequence package
generics
an implementation of generic functions, using selectors for dispatching and insertion.
messages
implements messages as specialized generic functions of arity one, possibly parametrized.
lazy-lists
lazy list implementation based on Moritz Heidkamp's lazy-seq. Contrary to Moritz' implementation, the lazy-list's length is stored in the datastructure, so that a distinction between finite and infinite lazy lists can be made.
treaps
A functional interface to Oleg Kiselyov's and Ivan Raikov's treap egg.
skiplists
An alternative to balanced search-trees.
random-access-lists
combine the advantages of linked lists (fast insert and remove) and vectors (fast access).
simple-tests
Some simple macros and commands which help debugging and testing.
continuations
Syntactic sugar for Marc Feeley's continuation interface providing i.a. catch and throw
simple-exceptions
An easy to use exception wrapper around chicken's condition system.
options
A variant of ML's option datatype, implemented as a functor producing typed modules and an untyped module.
simple-contracts
Design by contract for procedures
yasos
A Chicken port of Kenneth A. Dickey's "Yet another Scheme Object System".
Obsolete eggs
multi-methods
Implements a variant of generic functions, where arguments are checked against predicates to choose a matching procedure which is eventually invoked. A destinctive feature of this implementation is, that the client has complete control over the multi-methods state, a search tree, and can decide where to insert a procedure to be eventually invoked, so that more specific procedures are found before less specific ones. Hence, multi-methods can be used to implement OOP. But note, that dispatching is done on all arguments, not only the first one, as in traditional OOP-implementations. Deprecated, use generics instead.
cells
Simple implementation of the cell datatype, a lightweight variant of boxes. Deprecated, use simple-cells instead
list-bindings
Restricting some macros of the bindings egg to nested list expressions and supplying define-macro as an application. Obsolete, use bindings instead!
er-macros
Explicit renaming macros made easy. Obsolete, use bindings instead!
ir-macros
Implicit renaming macros made even easier. Obsolete, use bindings instead!
low-level-macros
Low level macros made easy. A merger of the two eggs er-macros and ir-macros. Obsolete, use bindings instead!
dbc
An implementation of "Design by Contract", coined by Bertrand Meyer for his Eiffel language. Now obsolete, use simple-contracts instead
contracts
My first implementation of "Design by Contract". Now obsolete, use dbc instead.