c09897c449
This is lighter-weight than building a full index->cursor table for the string, adding a constant two words to the memory required to store a string, as opposed to one word for every n characters. The cached cursor is used for any string-ref operation requesting an index after the most-recently-requested index, making potentially quadratic repeated string-ref procedures run in linear time. In theory, it could also use a heuristic to speed up moving backwards through the string when it thinks that moving the old cursor backwards would be faster than starting again at the start of the string. In practice, my logging of when the cached cursor is actually reused during the Chibi compilation and startup process shows that the most common case of moving backwards is going back to the start of the string anyway. Benchmarks to follow. |
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|---|---|---|
| .githooks | ||
| .github/workflows | ||
| benchmarks | ||
| build-lib/chibi/char-set | ||
| contrib | ||
| data | ||
| doc | ||
| examples | ||
| include/chibi | ||
| js | ||
| lib | ||
| opt | ||
| tests | ||
| tools | ||
| .gitignore | ||
| .hgignore | ||
| .travis.yml | ||
| appveyor.yml | ||
| AUTHORS | ||
| bignum.c | ||
| chibi-scheme.pc.in | ||
| CMakeLists.txt | ||
| configure | ||
| CONTRIBUTING.md | ||
| COPYING | ||
| eval.c | ||
| fedora.spec | ||
| gc.c | ||
| gc_heap.c | ||
| main.c | ||
| Makefile | ||
| Makefile.detect | ||
| Makefile.libs | ||
| mkfile | ||
| opcodes.c | ||
| plan9.c | ||
| README-win32.md | ||
| README.libs | ||
| README.md | ||
| RELEASE | ||
| sexp.c | ||
| simplify.c | ||
| TODO | ||
| VERSION | ||
| vm.c | ||
Minimal Scheme Implementation for use as an Extension Language
http://synthcode.com/wiki/chibi-scheme
Chibi-Scheme is a very small library intended for use as an extension and scripting language in C programs. In addition to support for lightweight VM-based threads, each VM itself runs in an isolated heap allowing multiple VMs to run simultaneously in different OS threads.
There are no external dependencies so is relatively easy to drop into any project.
Despite the small size, Chibi-Scheme attempts to do The Right Thing. The default settings include:
- a full numeric tower, with rational and complex numbers
- full and seamless Unicode support
- low-level and high-level hygienic macros
- an extensible module system
Specifically, the default repl language contains all bindings from
R7RS small, available explicitly as the
(scheme small) library. The language is built in layers, however -
see the manual for instructions on compiling with fewer features or
requesting a smaller language on startup.
Chibi-Scheme is known to work on 32 and 64-bit Linux, FreeBSD, NetBSD, OpenBSD and OS X, Plan 9, Windows, iOS, Android, ARM and Emscripten. Basic support for native Windows desktop also exists. See README-win32.md for details and build instructions.
To build on most platforms just run make && make test. This has a
few conditionals assuming GNU make. If using another make, there are
a few parameters in Makefile.detect you need to set by hand.
This will provide a shared library libchibi-scheme, as well as a sample chibi-scheme command-line repl. You can then run
sudo make install
to install the binaries and libraries. You can optionally specify a PREFIX for the installation directory:
make PREFIX=/path/to/install/
sudo make PREFIX=/path/to/install/ install
By default files are installed in /usr/local.
If you want to try out chibi-scheme without installing, be sure to set
LD_LIBRARY_PATH so it can find the shared libraries.
To make the emscripten build run make js (not emmake make js).
For more detailed documentation, run make doc and see the generated
doc/chibi.html.