STklos Home Page

Presentation

STklos is a free Scheme system compliant with the languages 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. STklos can also be compiled as a library and embedded in an application.

The salient points of STklos are:

an efficient and powerful object system based on CLOS providing
- Multiple Inheritance,
- Generic Functions,
- Multi-methods
- an efficient MOP (Meta Object Protocol)
a simple to use module system
a full tower of numbers implementation, as defined in R5RS,
easy connection to the GTK+ toolkit,
a Perl compatible regular expressions thanks to the PCRE package,
easily extensible with its ScmPkg mechanism,
it implements properly tail recursive calls.

Latest News

Version “1.40” released 2020-06-05

Changes in this version are:

Updated the build tools
Now STklos is case sensitive by default as required by R7RS the R5RS case insensitivity can be enable with the --case-insensitive option
New parameter: repl-theme permits to customize REPL prompt colors.
Added more tests
Added the #:xxx syntax for keywords for compatibility with other implementations
Added the R7RS syntaxes letrec, let-values & let-values
Various bug fixes

Version “1.31” released 2019-07-13

Bug fix version.

Changes in this version are:

Updated the version of the libraries included in the distribution
Bug fix of various problems when installing STklos
Bug fix for MacOs UTF8 detection
Added SRFI-112
Updated documentation

Version “1.30” released 2019-07-04

The goal of this version consists to be more R7RS compliant. All the R5RS functions which have been extended in R7RS are now conform to R7RS (for instance assoc and member accept now an optional parameter which is a compare function, vector->list accepts the start and end parameters, …)

Changes in this version are:

Implementations R7RS I/O
- Ports can now be binary or textual (standard ports are both)
- New functions:
  - write-string
  - wite-shared & write-simple
  - functions to input and output bytevectors
  - read-u8 peek-u8 and u8-ready?
  - call-with-port
  - textual-port?
  - binary-port?
  - open-binary-input-file
  - open-binary-output-file
  - utf8->string & string->utf8
Updated various functions to be R7RS compliant.
Added the R7RS functions on bytevectors
Added R7RS #true and #false constants
Added R7RS exceptions
Added R7RS system functions
Upgraded the libraries embedded in STklos source tree
Optimization of circular structure reading & writing
New primitives - display-simple & display-shared - R7RS symbol=? - R7RS boolean=?
Updated documentation
Added SRFI-111
Bug fixes

Version “1.20” released 2018-06-04

Even if previous version was released more than seven years ago, STklos is not completely dead.

Now the developement tree of STklos is available on Gitlab and Github.

Changes in this version are:

Corrected some problems on UTF8 encoding
Bug fix of a long standing bug on call/cc.
Function can now be created with the UTF8 symbol λ
Added the #!fold-case and #!no-fold-case special notations of R7RS
Updated documentation
Bug fixes

All the announces …