Log Message:
Update gauche to 0.9.5

Release Notes:

Better R7RS conformance

  * Keyword-symbol integration: Gauche keywords (e.g. :key) can be symbols
    that are automatically bound to itself. It breaks the backward
    compatibility in some corner cases, however, so we haven't make the
    change in effect by default in 0.9.5. Setting the environment variable
    GAUCHE_KEYWORD_IS_SYMBOL turns on this feature. See Keywords, for the
    details. We urge you to test your code with this feature turned on,
    for pretty soon (probably in the next release) we'll make this feature
    effective by default.
  * R7RS raise is now conformant of R7RS (which is slightly different from
    Gauche's builtin raise, which is srfi-18 conformant).

New modules and procedures

  * Renamed modules (old names are still valid, but new code should use
    the new names):
      + Data structure implementations are now named data.*; so
        util.queue, util.sparse, util.trie are renamed to data.queue,
        data.sparse, data.trie.
      + Module text.unicode is renamed to gauche.unicode, for it's
        essential for R7RS support.
  * New modules:
      + data.cache - Cache
      + data.heap - Heap
      + data.ring-buffer - Ring buffer
      + data.imap - Immutable map
      + data.ideque - Immutable deque
      + text.console: Simple console control module, works on both
        vt100-ish terminals and Windows console. Try examples/snake.scm to
        see it in action.
      + util.dominator - Find a dominator tree of a directed graph.
      + util.levenshtein - Calculate various edit-dinstances.
      + util.unification - Unification algorithm.
  * Low-level hygienic macro support by er-macro-transformer.
  * New builtin macros and procedures:
      + and-let1.
      + macroexpand-all - Expands everything in the given form.
      + sys-available-processors - query # of processor cores at runtime.
      + symbol-append.
      + sys-getgroups, sys-mkdtemp.
      + debug-label - Get unique label of an object.
      + length<?, length>?, length>=?, length=? - We had length<=?, \ 
so why
        not?
      + encode-float, inverse of decode-float.
  * In gauche.uvector:
      + New procedures:string->u32vector!, string->s32vector!,
        make-uvector, port->uvector
      + Generic accessor and mutator uvector-ref, uvector-set!.
  * In gauche.sequence:
      + New searching procedures - sequence-contains,
        break-list-by-sequence, break-list-by-sequence!, sequence->
        kmp-stepper.
      + New utilities - common-prefix, common-prefix-io.
  * In gauche.array: Add constructors u8array, etc., for the consistency.
  * In gauche.lazy: lappend-map
  * In gauche.generator: gflatten, uvector->generator.
  * In gauche.process:
      + run-process-pipeline - for easier pipelining.
      + shell-tokenize-string.
  * In gauche.termios: sys-termios-copy
  * In gauche.test:
      + test-none-of - As an expected value.
      + test-script - To test script files.
  * In gauche.vport: List ports are added. See open-input-char-list,
    open-input-byte-list.
  * In data.queue: mtqueue-num-waiting-readers.
  * In data.trie: trie-longest-match.
  * In data.random: samples$, for random sampling.
  * In text.csv: Middle-layer procedures: csv-rows->tuples,
    make-csv-header-parser, make-csv-record-parser.
  * In rfc.uri: uri-ref to access components of uri conveniently.
  * In rfc.http: http-status-code->description.

Added srfi supports

  * srfi-69: Basic hash tables
  * srfi-111: Boxes
  * srfi-112: Environment inquiry
  * srfi-113: Sets and Bags
  * srfi-114: Comparators
  * srfi-117: Mutable queues
  * srfi-118: Simple adjustable-size strings
  * srfi-121: Generators - Covered by gauche.generator.
  * srfi-128: Comparators (reduced) - the comparator is actually built-in
    to Gauche's core, so that other built-in mechanism such as hashtables,
    treemaps, sort, etc. can take comparators.
  * srfi-131: ERR5RS Record Syntax (reduced) - Subset of gauche.record.
  * srfi-133: Vector library
  * srfi-134: Immutable deques - Covered by data.ideque.

More pleasant interactive experience

  * Better error message while loading/compiling, using <mixin-condition>
    mechanism. Details.
  * Improved describe.
  * Toplevel REPL commands. See blog entry, or see the manual section
    "Working in REPL"
  * Scheme-defined procedures maintain source code and source location. It
    can be queried by source-code and source-location. The source location
    is also shown by describe. (Source code isn't kept for precompiled
    Scheme code for now.)
  * Online REPL document (info procedure, or ,info/,doc toplevel command)
    now shows just the named entry.
  * Experimental support of line-editing. If the environment variable
    GAUCHE_READ_EDIT is set and the terminal is capable, you can use line
    editing (with emacs-like key binding). This feature still in early
    development stage and has number of known issues---especially,
    multiline edit only partially work. If you're brave, give it a shot,
    but don't blame me if your REPL explodes.
  * You can invoke editor from repl by (ed file-or-procedure) (see ed). If
    the source location is known, you can directly jump to the source of
    the procedure, edit, and reload it.
  * Now REPL consumes the trailing newline of input S-expr; that is, when
    you type (read-line) on REPL, it waits for your input. Before, REPL
    didn't consume the trailing newline, so (read-line) immediately
    returned when it sees the newline character left in the input buffer,
    but that confused users.
  * use, select-module, export, import - Now these forms evaluate to zero
    values instead of #<undef>, for less cluttering of REPL.

Other notable improvements

  * gauche.configure: More feature tests on compilers and linking. Start
    using package.scm for the source of package metainformation.
  * Extended number syntax:
      + You can insert _ in prefixed numeric literal for readability, e.g.
        #b1101_1000_0001_1101.
      + Polar notation of numeric literal recognize pi suffix, e.g.
        2@0.5pi => 0.0+2.0i.
      + The reader recognizes CL-ish #<radix>r syntax, e.g. #3r121 for 121
        on base 3 (which is 16 in decimal).
  * Hashtables are now salted, meaning, it uses different hash functions
    at least for each invocation of the program, so that it is immune to
    the hash collision attack. The hash function is deprecated, replaced
    by default-hash, portable-hash and legacy-hash. See the manual entry
    for the details.
  * sys-sleep, sys-nanosleep: Changed to retry sleep/nanosleep by default
    if it is interrupted by as signal.
  * A new debug special reader macro: #?,, which can be used as #?,(proc
    arg ...). When evaluated, it displays the form (proc arg ...) and each
    value of arg, then calls proc with those arguments and displays the
    return value(s). Similar to #?= but you can also check the actual
    value of arguments. The #?= stub is also improved to show the thread
    from which it is displaying.
  * gauche.vport: open-output-uvector now takes an option to make the
    output buffer extendable.
  * load searches .sld suffix as well, as some other R7RS implementations
    do.
  * Stack trace now works for threads (but you have to call report-error
    within guard clauses explicitly, for by default unhandled error is
    propagated to the thread that calls thread-join!).
  * gauche.uvector: s8vector->string and u8vector->string now take
    optional 'terminator' argument, convenient to extract NUL-terminated
    string from fixed size buffer.
  * gauche.net: More flexible port number selection in make-server-socket
    and make-server-sockets.
  * data.sparse: Allow default value per vector (a sparse vector returns
    its default value when unset element is accessed).
  * rfc.http: Handles ipv6-style server address spec, e.g. [::1]:8888.
  * file.util: copy-file - Now takes :if-exists and :append keyword
    arguments.
  * crypt.bcrypt: Update bcrypt implementation and changed the default
    from 2a to 2b.
  * gauche.termios: Support mintty on MSYS.
  * rfc.tls: Add basic server-side certificate support.

Changes that may alter the behavior of existing code

  * gauche.generator: gtake - changed optional argument spec to match
    srfi-121. Existing code that needs the old behavior can use a new
    procedure gtake*.
  * If a hygienic macro inserts a fresh toplevel identifier, that
    identifier is renamed. E.g. if you say

    (define-syntax define-x (syntax-rules () ((_) (define x #t))))

    and then

    (define-x)

    the toplevel x is renamed and can't be referred to from outside. This
    is not explicitly specified in R7RS, but renaming is consistent with
    hygiene.
  * U+180e Mongolian Vowel Separator is no longer treated as a whitespace
    character, since Unicode 6.3.0 changed its category from Zs to Cf.
  * when, unless - Now they require at least one expr in their body.
  * require: Now loads a file into a special module, instead of #<module
    gauche>. This may catch an error that was previously ignored. See the
    manual entry for the details.
  * include, include-ci: Now relative pathnames, including ones that begin
    with ./ or ../, are taken relative to the includer file. Before, files
    beginning with ./ and ../ are treated specially, just like load. But
    it is less useful for include and just increases confusion.

Bug fixes

  * Fixed numerous bugs in hygienic macro expander.
  * When a module exports an inherited binding from renaming, it wasn't
    searched properly.
  * util.match: Fixed a bug that doesn't handle match expressions
    generated by hygienic macros.
  * Make -fcase-fold option affect REPL as well.
  * fixnum-width: It returned a number one smaller than the correct value.
  * Fixed a number reader bug handling very big or very small exponent.
  * srfi-13: Fixed a bug in xsubstring when 'from' argument is negative.
  * parameterize: Fixed a bug that failed to restore parameter values in
    some edge cases.