STklos Home page

Presentation

STklos (pronounced /ˈɛs.’ti.kl’ɔss/) is a free Scheme system mostly compliant with the language features defined in R⁷RS small. The aim of this implementation is to be fast as well as light. The implementation is based on an ad-hoc Virtual Machine.

The salient points of STklos are:

an efficient and powerful object system based on CLOS (Common Lisp Object System) providing
- Multiple Inheritance,
- Generic Functions,
- Multi-methods
- an efficient MOP (Meta Object Protocol)
a simple to use module system, as well as R⁷RS libraries
a full Numerical tower, as defined in R⁷RS,
a simple FFI (Foreign Function Interface),
an easy connection to the GTK+ toolkit,
a Perl compatible regular expressions thanks to the PCRE package,
Unicode support,
native threads built on top of Posix theads,
Tail Call Optimization, as required by R⁷RS,
Support for a large number of SRFIs.

Latest News

Version “2.00 released 2023-09-12

This is a major version of STklos, bringing it from R⁵RS to R⁷RS. It is the fruit of nearly two years of development with the help of the following persons (in alphabetical order):

Amirouche Boubekki (@amirouche)
Lassi Kortela (@lassik)
Ivan Maidanski (@ivmai)
Tom Niget (@zdimension)
Jeronimo Pellegrini (@jpellegrini)
Ryan Schmidt (@ryandesign)
Ben Taca (@bentaca)
Robby Zambito (@Zambito1)

The main changes in this version are:

Support for R⁷RS libraries
Macro system hash been rewritten
Support for ScmPkg packages has been suppressed
New options for the commands stklos(1) and stklos-compile(1)
Optimizations on numerical operations
Documentation is rewritten in asciidoctor and has been greatly enhanced
Updated the Docker build files
New instructions in the VM
Fixed some issues in the compilation/installation procedure
New extension: curl to access the multiprotocol file transfer library
Better support for macOS
describe has been enhanced for some type of objects
REPL has now tab completiongg
Bash and zsh completions for stklos and stklos-compile commands
Better SLIB support
Use PCRE2 library instead of legacy PCRE
New-command stklos-pp(1)
Better error messages
New SRFIS supported
- SRFI-19: Time Data Types and Procedures
- SRFI 43: Vector Library
- SRFI-95: Sorting and Merging
- SRFI 116: Immutable List Library
- SRFI 125: Intermediate hash tables
- SRFI-138: Compiling Scheme programs to executables
- SRFI 152: String Library (reduced)
- SRFI-162: Comparators sublibrary
- SRFI 154: First-class dynamic extents
- SRFI-215: Central Log Exchange
- SRFI 217: Integer Sets
- SRFI 222: Compound objects
- SRFI 224: Integer Mappings - Scheme Requests for Implementation
- SRFI-227: Optional Arguments
- SRFI 228: Composing Comparators
- SRFI-229: Tagged Procedures
- SRFI-230: Atomic Operations
- SRFI 235: Combinators
- SRFI 236: Evaluating expressions in an unspecified order
- SRFI-238: Codesets
- SRFI 244: Multiple-value Definitions
Added support for some R7RS-large libraries
- supported libraries of the Red edition are
  - (scheme bytevector)
  - (scheme box)
  - (scheme charset)
  - (scheme comparator)
  - (scheme generator)
  - (scheme hash-table)
  - (scheme ideque)
  - (scheme ilist)
  - (scheme list)
  - (scheme list-queue)
  - (scheme lseq)
  - (scheme set)
  - (scheme sort)
  - (scheme stream)
  - (scheme text)
  - (scheme vector)
- supported libraries of the Tangerine edition are
  - (scheme bitwise)
  - (scheme bytevector)
  - (scheme division)
  - (scheme fixnum)
  - (scheme flonum)
  - (scheme generator)
  - (scheme vector @)
New primitives
- library-name
- library-list
- module-list
- module-lock!
- module-locked?
- symbol-mutable?
- define-constant
- cpointer-null?
- syntax-error
- hash-table-clear!
- environement
- send-signal
- set-signal-handler!
- get-signal-handler
- void?
- procedure-source
- procedure-formals
- short-version
- radians->degrees
- degrees->radians
- sinh, cosh, …
New compiler options (also parameter objects):
- compiler:gen-line-number
- compiler:show-assembly-code
- compiler:time-display
- compiler:keep-formals
- compiler-keep-source
- compiler:inline-common-functions
- compiler:unroll-iterations
- repl-show-startup-message
New predefined classes
- <uvector>
- <bytevector>
- <hash-table>
- <port>
- <input-port>
- <output-port>
Code cleaning an optimizations
Added tests
Bug fixes

Version “1.70” released 2021-11-25

This version further improves compliance with R7RS and brings some new SRFIs

The main changes in this version are:

Added the some comma-commands to the REPL (,pwd ,cd and ,shell)
Use system Posix glob instead of the provided gnu-glob
Improved reader (|.| is wow valid symbol as well as numbers with bars)
New primitive/syntaxes
- tagbody
- repeat
- keyword-colon-position is a parameter object specifying the places where the colon can be used in keyword.
Suppressed the calls to insecure C function (such as strcpy or strcat)
List reading is tail recursive now
Added an extension directory, which contains for now:
- GTKlos which gives access to the GTK+ toolkit using the OO layer available in STklos. This version uses the GTK+3 toolkit. It also defines a canvas widget. if the to have the goocanvas library is installed.
- an extension which permits to make a file system in Scheme, using FUSE (Filesystem in Userspace).
Use gmp-mini (which is provided) if gmp is not available, instead of our version which was based on old unmaintained version of mpi.
Support of new SRFIs:
- SRFI-25: Multi-dimensional Arrays
- SRFI-27: Source of random bits
- SRFI-29: Localization
- SRFI-94: Type-Restricted Numerical Functions
- SRFI-132: Sort Libraries
- SRFI-133: Vector Library (R7RS-compatible)
- SRFI-143: Fixnums
- SRFI-144: Flonums
- SRFI-170: POSIX API
- SRFI-208: NaN procedures
- SRFI-214: Flexvectors
- SRFI-217: Integer Sets
- SRFI-219: Define higher-order lambda
- SRFI-223: Generalized binary search procedures
SRFI can be implemented in C and Scheme
Various optimizations
Documentation update
Added tests
Bug fixes

Version “1.60” released 2021-02-15

As the previous version, R7RS compliance is enhanced and a bunch of new SRFIS has been implemented (thanks again to Jeronimo Pellegrini — @jpellegrini).

Changes in this version are:

Added option -I and -A to prepend and append to the loadpath
New primitives/syntaxes
- require-feature
- define-values
Added makefile targets to install only subparts of STklos on constrained environments
Reader accepts now #i for rationals
Changed the version of LALR-SCM to version 2.5.0
Added scripts and documentation in the exemples directory
Definition of a new framework for implementing SRFIs
- Documentation of SRFI is now automatically built
- SRFI tests are automatically done with make tests
- Automatic update of the SUPPORTED-SRFIS file
Support of new SRFIs
- SRFI-5: A compatible let form with signatures and rest arguments
- SRFI-41: Streams
- SRFI-61: A more general COND clause
- SRFI-113: Sets and Bags
- SRFI-127: Lazy Sequences
- SRFI-128: Comparators (reduced)
- SRFI-130: Cursor-based string library
- SRFI-134: Immutable Deques
- SRFI-135: Immutable Texts
- SRFI-137: Minimal Unique Types
- SRFI-192: Port Positioning
- SRFI-193: Command line
- SRFI-195: Multiple-value boxes
- SRFI-196: Range Objects
- SRFI-207: String-notated bytevectors
- SRFI-216: SICP Prerequisites (Portable)
Documentations update
Added tests
Bug fixes

All the announces …