cyclone/docs/Features.md

Features

This page summarizes the Scheme language features implemented by Cyclone.

R⁷RS Compliance

This is the status of Scheme programming language features implemented from the R⁷RS Scheme Specification:

Section	Status	Comments
2.2 Whitespace and comments	Partial	No datum or block comments
2.3 Other notations	Partial	Not all of these notations are implemented
2.4 Datum labels	No
3.1 Variables, syntactic keywords, and regions	Yes
3.2 Disjointness of types	Yes
3.3 External representations	Yes
3.4 Storage model	Yes	No immutable types at this time.
3.5 Proper tail recursion	Yes
4.1 Primitive expression types	Partial	include and include-ci are not implemented, although include may be specified as part of a library definition.
4.2 Derived expression types	Partial	TODO: this is a large section. need to review support because most of this is included.
4.3 Macros	Partial	No support for syntax-rules but a lower-level explicit renaming macro system is implemented.
5.1 Programs	Yes
5.2 Import declarations	Partial
5.3 Variable definitions	Partial	define-values is not implemented yet.
5.4 Syntax definitions
5.5 Record-type definitions
5.6 Libraries	Partial	Support is "good enough" but need to make it more robust
5.7 The REPL	Yes
6.1 Equivalence predicates	Yes	eqv? is not implemented, it is just an alias to eq?
6.2 Numbers	Partial	Integers and reals are supported, but most numeric functions are missing at this time.
6.3 Booleans	Yes	#true and #false are not recognized by parser.
6.4 Pairs and lists	Yes	member functions are predicates, member and assoc do not accept compare argument.
6.5 Symbols	Yes
6.6 Characters	Partial	No unicode support, char-ci predicates are not implemented.
6.7 Strings	Partial	No unicode support, string-ci functions are not implemented.
6.8 Vectors	Yes
6.9 Bytevectors		Not supported yet.
6.10 Control features	Partial	The map and for-each families of functions only support one "data" argument - for example, string-map only accepts one string. values and call-with-values are not implemented. dynamic-wind is limited, and does not work across calls to continuations.
6.11 Exceptions	Partial	Exceptions are implemented but error objects (and associated functions error-object, etc) are not at this time.
6.12 Environments and evaluation	Partial	Only eval is implemented at this time.
6.13 Input and output	Partial	Functions do not differentiate between binary and textual ports. Do not have support for input/output strings or bytevectors.
6.14 System interface	Yes

R⁷RS Libraries

TODO: list each supported library here, and link to a separate page with that library's API as implemented by Cyclone

• scheme base
• scheme char
• scheme eval
• scheme file
• scheme load
• scheme process-context
• scheme read
• scheme time
• scheme write

SRFI Support

Cyclone supports the following Scheme Requests for Implementation (SRFI) libraries:

TODO: SRFI 18 - Multithreading support

Cyclone-specific

Cyclone also supports several non-standard features:

• system
• what else?

FFI

TODO