CHANGES

Change Log
----------

Version 1.50
    - extended the public API and properly namespaced everything
    - separated the main tinyscheme shell into a separate file
    - made source compatible with Visual C++ (and consequently C89)
    - added regex module and updated it to use the new API

Version 1.41
    Bugs fixed:
        #3020389 - Added makefile section for Mac OS X  (SL)
        #3286135 - Fixed num_mod routine which caused errors in use of modulo
        #3290232 - Corrected version number shown on startup  (GM)
        #3394882 - Added missing #if in opdefines.h around get and put  (DC)
        #3395547 - Fix for the modulo procedure  (DC)
        #3400290 - Optimized append to make it an O(n) operation  (DC)
        #3493926 - Corrected flag used when building shared files on OSX (J)

    R5RS related changes:
        #2866196 - Parser does not handle delimiters correctly
        #3395548 - Add a decimal point to inexact numbers in atom2str  (DC)
        #3399331 - Make min/max return inexact when any argument is inexact
        #3399332 - Compatability fix for expt.
        #3399335 - Optional radix for string->number and number->string  (DC)
        #3400202 - Append with one argument should not return a list  (DC)
        #3400284 - Compatability fix for integer?

    Other changes:
        - Added flags to makefile for MinGW/MSYS (TC)
        - Moved variable declarations to avoid warnings with some compilers
        - Don't print space after initial #( when printing vectors.
        - Minor optimization for is_nonneg().
        - No need to round integers in OP_ROUND (#3400284)
        - Fixes to code that reports line number with error  (RC)

    Contributors:
        Kevin Cozens, Gordon McNutt, Doug Currie, Sean Long, Tim Cas, Joey,
        Richard Copley, and CMarinier.

Version 1.40
    Bugs fixed:
        #1964950 - Stop core dumps due to bad syntax in LET (and variants)
        #2826594 - allow reverse to work on empty list (Tony Garnock-Jones)
        Potential problem of arglist to foreign calls being wrongly GC'ed.
        Fixed bug that read could loop forever (tehom).

    API changes:
        Exposed is_list and list_length.
        Added scheme_register_foreign_func_list and declarations for it (tehom)
        Defined *compile-hook* (tehom)

    Other changes:
        Updated is_list and list_length to handle circular lists.
        Nested calling thru C has been made now safer (tehom)
        Peter Michaux cleaned up port_rep_from_file
        Added unwind-protect (tehom)
        Some cleanups to in/outport and Eval_Cycle by Peter Michaux
        Report error line number (Mostly by Sanel Zukan, back-compatibility by Tehom)

    Contributors:
        Kevin Cozens, Dimitrios Souflis, Tom Breton, Peter Michaux, Sanel Zukan,
        and Tony Garnock-Jones.

Version 1.39
    Bugs fixed:
        Fix for the load bug
        Fixed parsing of octal coded characters. Fixes bug #1818018.
        Added tests for when mk_vector is out of memory. Can't rely on sc->sink.
        Fix for bug #1794369
        Finished feature-request 1599947: scheme_apply0 etc return values.
        Partly provided feature-request 1599947: Expose list_length, eqv, etc
        Provided feature-request 1599945, Scheme->C->Scheme calling.
        Fix for bug 1593861 (behavior of is_integer)
        Fix for bug 1589711
        Error checking of binding spec syntax in LET and LETREC. The bad syntax
        was causing a segmentation fault in Linux. Complete fixes for bug #1817986.
        Error checking of binding spec syntax in LET*
        Bad syntax was causing core dump in Linux.
        Fix for nasty gc bug

    R5RS changes:
        R5RS requires numbers to be of equal value AND of the same type (ie. both
        exact or inexact) in order to return #t from eqv?. R5RS compliance fix.
        String output ports now conform to SRFI-6

    Other changes:
        Drew Yao fixed buffer overflow problems in mk_sharp_const.
        put OP_T0LVL in charge of reacting to EOF
        file_push checks array bounds (patch from Ray Lehtiniemi)
        Changed to always use snprintf (Patch due to Ramiro bsd1628)
        Updated usage information using text from the Manual.txt file.

Version 1.38
    Interim release until the rewrite, mostly incorporating modifications
    from Kevin Cozens. Small addition for Cygwin in the makefile, and
    modifications by Andrew Guenther for Apple platforms.

Version 1.37
    Joe Buehler submitted reserve_cells.

Version 1.36
    Joe Buehler fixed a patch in the allocator.
    Alexander Shendi moved the comment handling in the scanner, which
    fixed an obscure bug for which Mike E had provided a patch as well.
    Kevin Cozens has submitted some fixes and modifications which have
    not been incorporated yet in their entirety.

Version 1.35
    Todd Showalter discovered that the number of free cells reported
    after GC was incorrect, which could also cause unnecessary allocations.

Version 1.34
    Long missing version. Lots of bugfixes have accumulated in my email, so
    I had to start using them. In this version, Keenan Pepper has submitted
    a bugfix for the string comparison library procedure, Wouter Boeke
    modified some code that was casting to the wrong type and crashed on
    some machines, "SheppardCo" submitted a replacement "modulo" code and
    Scott Fenton submitted lots of corrections that shut up some compiler
    warnings. Brian Maher submitted instructions on how to build on OS-X.
    I have to dig deeper into my mailbox and find earlier emails, too.

Version 1.33
    Charles Hayden fixed a nasty GC bug of the new stack frame, while in
    the process of porting TinyScheme to C++. He also submitted other
    changes, and other people also had comments or requests, but the GC
    bug was so important that this version is put through the door to
    correct it.

Version 1.32
    Stephen Gildea put some quality time on TinyScheme again, and made
    a whole lot of changes to the interpreter that made it noticeably
    faster.

Version 1.31
    Patches to the hastily-done version 1.30. Stephen Gildea fixed
    some things done wrongly, and Richard Russo fixed the makefile
    for building on Windows. Property lists (heritage from MiniScheme)
    are now optional and have dissappeared from the interface. They
    should be considered as deprecated.

Version 1.30
    After many months, I followed Preston Bannister's advice of
    using macros and a single source text to keep the enums and the
    dispatch table in sync, and I used his contributed "opdefines.h".
    Timothy Downs contributed a helpful function, "scheme_call".
    Stephen Gildea contributed new versions of the makefile and
    practically all other sources. He created a built-in STRING-APPEND,
    and fixed a lot of other bugs.
    Ruhi Bloodworth reported fixes necessary for OS X and a small
    bug in dynload.c.

Version 1.29
    The previous version contained a lot of corrections, but there
    were a lot more that still wait on a sheet of paper lost in a
    carton someplace after my house move... Manuel Heras-Gilsanz
    noticed this and resent his own contribution, which relies on
    another bugfix that v.1.28 was missing: a problem with string
    output, that this version fixes. I hope other people will take
    the time to resend their contributions, if they didn't make it
    to v.1.28.

Version 1.28
    Many people have contacted me with bugfixes or remarks in
    the three months I was inactive. A lot of them spotted that
    scheme_deinit crashed while reporting gc results. They suggested
    that sc->outport be set to NIL in scheme_deinit, which I did.
    Dennis Taylor remarked that OP_VALUEPRINT reset sc->value instead
    of preserving it. He submitted a modification which I adopted
    partially. David Hovemeyer sent me many little changes, that you
    will find in version 1.28, and Partice Stoessel modified the
    float reader to conform to R5RS.

Version 1.27
    Version 1.27 is the successor of 1.25. Bug fixes only, but I had to
    release them so that everybody can profit. 'Backchar' tried to write
    back to the string, which obviously didn't work for const strings.
    'Substring' didn't check for crossed start and end indices. Defines
    changed to restore the ability to compile under MSVC.

Version 1.26
    Version 1.26 was never released. I changed a lot of things, in fact
    too much, even the garbage collector, and hell broke loose. I'll
    try a more gradual approach next time.

Version 1.25
    Types have been homogenized to be able to accommodate a different
    representation. Plus, promises are no longer closures. Unfortunately,
    I discovered that continuations and force/delay do not pass the SCM
    test (and never did)... However, on the bright side, what little
    modifications I did had a large impact on the footprint:
    USE_NO_FEATURES now produces an object file of 63960 bytes on Linux!

Version 1.24
    SCM tests now pass again after change in atom2str.

Version 1.23
    Finally I managed to mess it up with my version control. Version
    1.22 actually lacked some of the things I have been fixing in the
    meantime. This should be considered as a complete replacement for
    1.22.

Version 1.22
    The new ports had a bug in LOAD. MK_CLOSURE is introduced.
    Shawn Wagner inquired about string->number and number->string.
    I added string->atom and atom->string and defined the number
    functions from them. Doing that, I fixed WRITE applied to symbols
    (it didn't quote them). Unfortunately, minimum build is now
    slightly larger than 64k... I postpone action because Jason's idea
    might solve it elegantly.

Version 1.21
    Jason Felice submitted a radically different datatype representation
    which he had implemented. While discussing its pros and cons, it
    became apparent that the current implementation of ports suffered
    from a grave fault: ports were not garbage-collected. I changed the
    ports to be heap-allocated, which enabled the use of string ports
    for loading. Jason also fixed errors in the garbage collection of
    vectors. USE_VERBATIM is gone. "ssp_compiler.c" has a better solution
    on HTML generation. A bug involving backslash notation in strings
    has been fixed. '-c' flag now executes next argument as a stream of
    Scheme commands. Foreign functions are now also heap allocated,
    and scheme_define is used to define everything.

Version 1.20
    Tracing has been added. The toplevel loop has been slightly
    rearranged. Backquote reading for vector templates has been
    sanitized. Symbol interning is now correct. Arithmetic functions
    have been corrected. APPLY, MAP, FOR-EACH, numeric comparison
    functions fixed. String reader/writer understands \xAA notation.

Version 1.19
    Carriage Return now delimits identifiers. DOS-formatted Scheme files
    can be used by Unix. Random number generator added to library.
    Fixed some glitches of the new type-checking scheme. Fixed erroneous
    (append '() 'a) behavior. Will continue with r4rstest.scm to
    fix errors.

Version 1.18
    The FFI has been extended. USE_VERBOSE_GC has gone. Anyone wanting
    the same functionality can put (gcverbose #t) in init.scm.
    print-width was removed, along with three corresponding op-codes.
    Extended character constants with ASCII names were added.
    mk_counted_string paves the way for full support of binary strings.
    As much as possible of the type-checking chores were delegated
    to the inner loop, thus reducing the code size to less than 4200 loc!

Version 1.17
    Dynamically-loaded extensions are more fully integrated.
    TinyScheme is now distributed under the BSD open-source license.

Version 1.16
    Dynamically-loaded extensions introduced (USE_DL).
    Santeri Paavolainen found a race condition: When a cons is executed,
    and each of the two arguments is a constructing function,  GC could
    happen before all arguments are evaluated and cons() is called, and
    the evaluated arguments would all be reclaimed!
    Fortunately, such a case was rare in the code, although it is
    a pitfall in new code and code in foreign functions. Currently, only
    one such case remains, when COLON_HOOK is defined.

Version 1.15
    David Gould also contributed some changes that speed up operation.
    Kirk Zurell fixed HASPROP.
    The Garbage Collection didn't collect all the garbage...fixed.

Version 1.14
    Unfortunately, after Andre fixed the GC it became obvious that the
    algorithm was too slow... Fortunately, David Gould found a way to
    speed it up.

Version 1.13
    Silly bug involving division by zero resolved by Roland Kaufman.
    Macintoch support from Shmulik Regev.
    Float parser bug fixed by Alexander Shendi.
    GC bug from Andru Luvisi.

Version 1.12
    Cis* incorrectly called isalpha() instead of isascii()
    Added USE_CHAR_CLASSIFIERS, USE_STRING_PORTS.

Version 1.11
    BSDI defines isnumber... changed all similar functions to is_*
    EXPT now has correct definition. Added FLOOR,CEILING,TRUNCATE
    and ROUND, courtesy of Bengt Kleberg. Preprocessor symbols now
    have values 1 or 0, and can be set as compiler defines (proposed
    by Andy Ganor *months* ago). 'prompt' and 'InitFile' can now be
    defined during compilation, too.

Version 1.10
    Another bug when file ends with comment!
    Added DEFINE-MACRO in init.scm, courtesy of Andy Gaynor.

Version 1.09
    Removed bug when READ met EOF. lcm.

Version 1.08
    quotient,remainder and modulo. gcd.

Version 1.07
    '=>' in cond now exists
    list? now checks for circularity
    some reader bugs removed
    Reader is more consistent wrt vectors
    Quote and Quasiquote work with vectors

Version 1.06
    #! is now skipped
    generic-assoc bug removed
    strings are now managed differently, hack.txt is removed
    various delicate points fixed

Version 1.05
    Support for scripts, *args*, "-1" option.
    Various R5RS procedures.
    *sharp-hook*
    Handles unmatched parentheses.
    New architecture for procedures.

Version 1.04
    Added missing T_ATOM bits...
    Added vectors
    Free-list is sorted by address, since vectors need consecutive cells.
    (quit <exitcode>) for use with scripts

Version 1.03 (26 Aug 1998):
    Extended .h with useful functions for FFI
    Library: with-input-* etc.
    Finished R5RS I/O, added string ports.

Version 1.02 (25 Aug 1998):
    First part of R5RS I/O.