Here is the latest OCaml Weekly News, for the week of April 22 to 29, 2014.
Archive: https://sympa.inria.fr/sympa/arc/caml-list/2014-04/msg00162.htmlDaniel de Rauglaudre announced:
Camlp5 sources are now distributed in a git directory. Useful if you are a user of Camlp5 and want to test your software against the current (trunk) version of OCaml or in case of fixed bugs or new features of Camlp5 not yet released. To get it, type in a terminal: git clone git://scm.gforge.inria.fr/camlp5/camlp5.git Then you get Camlp5 sources in a directory named camlp5. To update, when changes are done later, go to this directory and type: git pull
Archive: https://sympa.inria.fr/sympa/arc/caml-list/2014-04/msg00167.htmlJeremie Dimino announced:
I am pleased to announce the 111.11.00 release of the Core suite. The following packages were upgraded: - async - async_extra - async_kernel - async_unix - core - core_extended - core_kernel - ocaml_plugin - sexplib Files and documentation for this release are available on our website and all packages are in opam: https://ocaml.janestreet.com/ocaml-core/111.11.00/individual/ https://ocaml.janestreet.com/ocaml-core/111.11.00/doc/ Here is the changelog for this version: # 111.11.00 ## async - Updated the sound.ml example ## async_extra - Made `Log` more fair with respect to other Async jobs, by working on fixed-length groups of incoming log messages. Previously, `Log` had processed everything available. The change gives other Async jobs more of a chance to run. ## async_kernel - Added `Clock.run_at_intervals`, which runs a job at regular intervals. ## async_unix - Added `val Scheduler.yield : unit -> unit Deferred.t`, which becomes determined after the current cycle finishes. - Improved the behavior of the scheduler's thread pool when `Thread.create` raises. With this improvement, when the thread pool is unable to create a thread, it presses on with the threads it has rather than raise. Subsequent attempts to add work to the thread pool will cause the pool to attempt to create the thread, as long as enough time has passed since the most recent thread-creation failure. Before this change, the thread pool wouldn't handle a `Thread.create` exception, and the exception would get raised to whatever code happened to be calling the `Thread_pool` function that tried to create a thread, e.g. `Thread_pool.add_work`. This caused `In_thread.run` to unexpectedly raise, and in turn `In_thread.syscall` to unexpectedly raise, leading to: ``` "Fd.syscall_in_thread bug -- should be impossible" ``` Also, changed `should be impossible` text to `please report`, since there may be other lurking rare exceptions that `In_thread.syscall` can raise, and we'd like to hear about them. We rely on thread-pool-stuck detection to report problems where the inability to create threads causes the inability of the thread pool to make progress. A tweak was needed to make that work -- now the thread-pool-stuck warning is based on whether the thread pool has unstarted work, rather than on whether the thread pool has an "available thread". The latter would no longer work, since it is now possible for the thread pool to have unstarted work and to appear to have an available thread, i.e. `num_threads < max_num_threads`. ## core - Change some `Bigstring` functions to retry on `EINTR` rather than raise. The following functions (and their unsafe versions) were affected: * `read` * `really_read` * `really_recv` * `really_write` * `really_send_no_sigpipe` Some other `Bigstring` functions, like `input` and `output`, already retried on `EINTR`, so this change has precedent. All of the affected stubs raise `Bigstring.IOError` on failure, rather than `Unix_error`, which means the normal method for retrying on `EINTR` doesn't work. In particular `Async.Reader` didn't retry them, even though it was supposed to. Additionally, the documentation for the following functions was corrected to say that they raise =Unix_error= rather than =IOError=: * `pread_assume_fd_is_nonblocking` * `pwrite_assume_fd_is_nonblocking` - Eliminated global binary-to-decimal tables computed at startup for converting `Date` and `Of_day` to string. Used an efficient implementation of division by 10, rather than the `sprintf` tables in `time_internal.ml`. This result in much less allocation at startup and it is a bit faster: * before: | Name | Time/Run | mWd/Run | Percentage | |----------------+----------+---------+------------| | Date.to_string | 69.39ns | 3.00w | 100.00% | - after: | Name | Time/Run | mWd/Run | Percentage | |----------------+----------+---------+------------| | Date.to_string | 53.38ns | 3.00w | 100.00% | - Fixed `Time.Zone` tests so that they are deterministic. - Added `Iobuf.to_string_hum`, which produces a readable, multi-line representation of an iobuf, intended for debugging. - Fixed brittle unit tests of `Command`. ## core_extended - For `Flang`, added ordering to fields, and added `abs`, `min`, and `max` to the language. - Removed `Loggers` module. ## core_kernel - Added to `String` functions for substring search and replace, based on the KMP algorithm. Here are some benchmarks, comparing `Re2` for a fixed pattern, Mark's kmp from extended_string, and this implementation ("needle"). The pattern is the usual `abacabadabacabae...`. The text looks similar, with the pattern occurring at the very end. For =Re2= and =Needle= search benchmarks, the pattern is preprocessed in advance, outside of the benchmark. FWIW: I've also tried searches with pattern size = 32767, but =Re2= blows up, saying: ``` re2/dfa.cc:447: DFA out of memory: prog size 32771 mem 2664898 ``` | Name | Time/Run | mWd/Run | mjWd/Run | Prom/Run | Percentage | |-------------------------------+-----------------+---------------+-------------+----------+------------| | create_needle_15 | 102.56ns | 21.00w | | | | | re2_compile_15 | 6_261.48ns | | 3.00w | | 0.01% | | create_needle_1023 | 13_870.48ns | 5.00w | 1_024.01w | | 0.03% | | re2_compile_1023 | 107_533.32ns | | 3.03w | | 0.24% | | create_needle_8191 | 90_107.02ns | 5.00w | 8_192.01w | | 0.20% | | re2_compile_8191 | 1_059_873.47ns | | 3.28w | 0.28w | 2.37% | | create_needle_524287 | 6_430_623.96ns | 5.00w | 524_288.09w | | 14.35% | | | | | | | | | re2_compile_524287 | 44_799_605.83ns | | 3.77w | 0.77w | 100.00% | | needle_search_15_95 | 349.65ns | 4.00w | | | | | re2_search_15_95 | 483.11ns | | | | | | mshinwell_search_15_95 | 1_151.38ns | 781.01w | | | | | needle_search_15_815 | 2_838.85ns | 4.00w | | | | | re2_search_15_815 | 3_293.06ns | | | | | | mshinwell_search_15_815 | 8_360.57ns | 5_821.07w | 0.55w | 0.55w | 0.02% | | needle_search_15_2415 | 8_395.84ns | 4.00w | | | 0.02% | | re2_search_15_2415 | 9_594.14ns | | | | 0.02% | | mshinwell_search_15_2415 | 24_602.09ns | 17_021.16w | 1.62w | 1.62w | 0.05% | | needle_search_1023_6143 | 14_825.50ns | 4.00w | | | 0.03% | | re2_search_1023_6143 | 40_926.59ns | | | | 0.09% | | mshinwell_search_1023_6143 | 81_930.46ns | 49_149.66w | 1_025.65w | 1.65w | 0.18% | | needle_search_1023_52223 | 126_465.96ns | 4.00w | | | 0.28% | | re2_search_1023_52223 | 365_359.98ns | | | | 0.82% | | mshinwell_search_1023_52223 | 527_323.73ns | 371_715.39w | 1_033.17w | 9.17w | 1.18% | | needle_search_1023_154623 | 377_539.53ns | 4.00w | | | 0.84% | | re2_search_1023_154623 | 1_001_251.93ns | | | | 2.23% | | mshinwell_search_1023_154623 | 1_499_835.01ns | 1_088_518.15w | 1_033.19w | 9.19w | 3.35% | | needle_search_8191_49151 | 115_223.31ns | 4.00w | | | 0.26% | | re2_search_8191_49151 | 559_487.38ns | | | | 1.25% | | mshinwell_search_8191_49151 | 653_981.19ns | 393_219.50w | 8_201.01w | 9.01w | 1.46% | | needle_search_8191_417791 | 976_725.24ns | 4.00w | | | 2.18% | | re2_search_8191_417791 | 4_713_965.69ns | | | | 10.52% | | mshinwell_search_8191_417791 | 4_224_417.93ns | 2_973_709.32w | 8_202.37w | 10.37w | 9.43% | | needle_search_8191_1236991 | 2_912_863.78ns | 4.00w | | | 6.50% | | re2_search_8191_1236991 | 14_039_230.59ns | | | | 31.34% | | mshinwell_search_8191_1236991 | 11_997_713.73ns | 8_708_130.87w | 8_202.47w | 10.47w | 26.78% | - Added to `Set` functions for converting to and from a `Map.t`. ```ocaml val to_map : ('key, 'cmp) t -> f:('key -> 'data) -> ('key, 'data, 'cmp) Map.t val of_map_keys : ('key, _, 'cmp) Map.t -> ('key, 'cmp) t ``` This required adding some additional type trickery to `Core_set_intf` to indicate that the comparator for a given module may or may not be fixed. - Added an optional `iter` parameter to `Container.Make`. A direct implementation of `iter` is often more efficient than defining `iter` in terms of `fold`, and in these cases, the results of `Container.Make` that are defined in terms of `iter` will be more efficient also. - Added `Int.pow` (and for other integer types), for bounds-checked integer exponentiation. ## ocaml_plugin - Added a tag to exceptions coming from the toplevel execution of plugins so that we do not confuse them with exceptions coming from the library. Also, added a function to check a plugin without executing it. And captured the common pattern of checking the compilation of a plugin in a `Command.t` offered in the library. ## sexplib - Added error locations to `Macro`-expansion errors.
Archive: https://sympa.inria.fr/sympa/arc/caml-list/2014-04/msg00188.htmlDaniel Bünzli announced:
There was still a bug in the initialization of the rank S.switch'ed signals which wasn't captured by the test suite. It now is and we have react 1.1.0. A few new combinators (e.g. for dealing with options) were also added. Details here: https://github.com/dbuenzli/react/blob/master/CHANGES.md
Thanks to Alp Mestan, we now include in the OCaml Weekly News the links to the recent posts from the ocamlcore planet blog at http://planet.ocaml.org/. Writing Planet in pure OCaml: http://amirchaudhry.com/writing-planet-in-pure-ocaml Being normal: http://shayne-fletcher.blogspot.com/2014/04/being-normal.html Power means: http://shayne-fletcher.blogspot.com/2014/03/power-means.html Program Analysis Software Developer at ForAllSecure (Full-time): http://functionaljobs.com/jobs/8707-program-analysis-software-developer-at-forallsecure Full Time: Software Developer (Functional Programming) at Jane Street in New York, NY; London, UK; Hong Kong: http://jobs.github.com/positions/0a9333c4-71da-11e0-9ac7-692793c00b45 Fifth OCaml compiler hacking session: http://ocamllabs.github.com/compiler-hacking/2014/04/24/fifth-compiler-hacking-session.html How to fail - introducing Or_error.t: https://blogs.janestreet.com/how-to-fail-introducing-or-error-dot-t/?utm_source=rss&utm_medium=rss&utm_campaign=how-to-fail-introducing-or-error-dot-t
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