src/vendor/itertools/README.rst

   1
   2 Itertools
   3 =========
   4
   5 Extra iterator adaptors, functions and macros.
   6
   7 Please read the `API documentation here`__
   8
   9 __ https://docs.rs/itertools/
  10
  11 |build_status|_ |crates|_
  12
  13 .. |build_status| image:: https://travis-ci.org/bluss/rust-itertools.svg?branch=master
  14 .. _build_status: https://travis-ci.org/bluss/rust-itertools
  15
  16 .. |crates| image:: http://meritbadge.herokuapp.com/itertools
  17 .. _crates: https://crates.io/crates/itertools
  18
  19 How to use with cargo:
  20
  21 .. code:: toml
  22
  23     [dependencies]
  24     itertools = "0.7.3"
  25
  26 How to use in your crate:
  27
  28 .. code:: rust
  29
  30     #[macro_use] extern crate itertools;
  31
  32     use itertools::Itertools;
  33
  34 How to contribute:
  35
  36 - Fix a bug or implement a new thing
  37 - Include tests for your new feature, preferably a quickcheck test
  38 - Make a Pull Request
  39
  40
  41 Recent Changes
  42 --------------
  43
  44 - 0.7.6
  45
  46   - Add new adaptor ``.multi_cartesian_product()`` which is an n-ary product
  47     iterator by @tobz1000
  48   - Add new method ``.sorted_by_key()`` by @Xion
  49   - Provide simpler and faster ``.count()`` for ``.unique()`` and ``.unique_by()``
  50
  51 - 0.7.5
  52
  53   - ``.multipeek()`` now implements ``PeekingNext``, by @nicopap.
  54
  55 - 0.7.4
  56
  57   - Add new adaptor ``.update()`` by @lucasem; this adaptor is used
  58     to modify an element before passing it on in an iterator chain.
  59
  60 - 0.7.3
  61
  62   - Add new method ``.collect_tuple()`` by @matklad; it makes a tuple out of
  63     the iterator's elements if the number of them matches **exactly**.
  64   - Implement ``fold`` and ``collect`` for ``.map_results()`` which means
  65     it reuses the code of the standard ``.map()`` for these methods.
  66
  67 - 0.7.2
  68
  69   - Add new adaptor ``.merge_join_by`` by @srijs; a heterogeneous merge join
  70     for two ordered sequences.
  71
  72 - 0.7.1
  73
  74   - Iterator adaptors and iterators in itertools now use the same ``must_use``
  75     reminder that the standard library adaptors do, by @matematikaedit and @bluss
  76     *“iterator adaptors are lazy and do nothing unless consumed”*.
  77
  78 - 0.7.0
  79
  80   - Faster ``izip!()`` by @krdln
  81
  82     - ``izip!()`` is now a wrapper for repeated regular ``.zip()`` and
  83       a single ``.map()``. This means it optimizes as well as the standard
  84       library ``.zip()`` it uses.
  85       **Note:** ``multizip`` and ``izip!()`` are now different! The former
  86       has a named type but the latter optimizes better.
  87
  88   - Faster ``.unique()``
  89
  90   - ``no_std`` support, which is opt-in!
  91
  92     - Many lovable features are still there without std, like ``izip!()``
  93       or ``.format()`` or ``.merge()``, but not those that use collections.
  94
  95   - Trait bounds were required up front instead of just on the type:
  96     ``group_by``'s ``PartialEq`` by @Phlosioneer and ``repeat_call``'s
  97     ``FnMut``.
  98   - Removed deprecated constructor ``Zip::new`` — use ``izip!()`` or ``multizip()``
  99
 100 - 0.6.5
 101
 102   - Fix bug in ``.cartesian_product()``'s fold (which only was visible for
 103     unfused iterators).
 104
 105 - 0.6.4
 106
 107   - Add specific ``fold`` implementations for ``.cartesian_product()`` and
 108     ``cons_tuples()``, which improves their performance in fold, foreach, and
 109     iterator consumers derived from them.
 110
 111 - 0.6.3
 112
 113   - Add iterator adaptor ``.positions(predicate)`` by @tmccombs
 114
 115 - 0.6.2
 116
 117   - Add function ``process_results`` which can “lift” a function of the regular
 118     values of an iterator so that it can process the ``Ok`` values from an
 119     iterator of ``Results`` instead, by @shepmaster
 120   - Add iterator method ``.concat()`` which combines all iterator elements
 121     into a single collection using the ``Extend`` trait, by @srijs
 122
 123 - 0.6.1
 124
 125   - Better size hint testing and subsequent size hint bugfixes by @rkarp.
 126     Fixes bugs in product, interleave_shortest size hints.
 127   - New iterator method ``.all_equal()`` by @phimuemue
 128
 129 - 0.6.0
 130
 131   - Deprecated names were removed in favour of their replacements
 132   - ``.flatten()`` does not implement double ended iteration anymore
 133   - ``.fold_while()`` uses ``&mut self`` and returns ``FoldWhile<T>``, for
 134     composability (#168)
 135   - ``.foreach()`` and ``.fold1()`` use ``self``, like ``.fold()`` does.
 136   - ``.combinations(0)`` now produces a single empty vector. (#174)
 137
 138 - 0.5.10
 139
 140   - Add itertools method ``.kmerge_by()`` (and corresponding free function)
 141   - Relaxed trait requirement of ``.kmerge()`` and ``.minmax()`` to PartialOrd.
 142
 143 - 0.5.9
 144
 145   - Add multipeek method ``.reset_peek()``
 146   - Add categories
 147
 148 - 0.5.8
 149
 150   - Add iterator adaptor ``.peeking_take_while()`` and its trait ``PeekingNext``.
 151
 152 - 0.5.7
 153
 154   - Add iterator adaptor ``.with_position()``
 155   - Fix multipeek's performance for long peeks by using ``VecDeque``.
 156
 157 - 0.5.6
 158
 159   - Add ``.map_results()``
 160
 161 - 0.5.5
 162
 163   - Many more adaptors now implement ``Debug``
 164   - Add free function constructor ``repeat_n``. ``RepeatN::new`` is now
 165     deprecated.
 166
 167 - 0.5.4
 168
 169   - Add infinite generator function ``iterate``, that takes a seed and a
 170     closure.
 171
 172 - 0.5.3
 173
 174   - Special-cased ``.fold()`` for flatten and put back. ``.foreach()``
 175     now uses fold on the iterator, to pick up any iterator specific loop
 176     implementation.
 177   - ``.combinations(n)`` asserts up front that ``n != 0``, instead of
 178     running into an error on the second iterator element.
 179
 180 - 0.5.2
 181
 182   - Add ``.tuples::<T>()`` that iterates by two, three or four elements at
 183     a time (where ``T`` is a tuple type).
 184   - Add ``.tuple_windows::<T>()`` that iterates using a window of the
 185     two, three or four most recent elements.
 186   - Add ``.next_tuple::<T>()`` method, that picks the next two, three or four
 187     elements in one go.
 188   - ``.interleave()`` now has an accurate size hint.
 189
 190 - 0.5.1
 191
 192   - Workaround module/function name clash that made racer crash on completing
 193     itertools. Only internal changes needed.
 194
 195 - 0.5.0
 196
 197   - `Release announcement <http://bluss.github.io/rust/2016/09/26/itertools-0.5.0/>`_
 198   - Renamed:
 199
 200     - combinations is now tuple_combinations
 201     - combinations_n to combinations
 202     - group_by_lazy, chunks_lazy to group_by, chunks
 203     - Unfold::new to unfold()
 204     - RepeatCall::new to repeat_call()
 205     - Zip::new to multizip
 206     - PutBack::new, PutBackN::new to put_back, put_back_n
 207     - PutBack::with_value is now a builder setter, not a constructor
 208     - MultiPeek::new, .multipeek() to multipeek()
 209     - format to format_with and format_default to format
 210     - .into_rc() to rciter
 211     - ``Partition`` enum is now ``Either``
 212
 213   - Module reorganization:
 214
 215     - All iterator structs are under ``itertools::structs`` but also
 216       reexported to the top level, for backwards compatibility
 217     - All free functions are reexported at the root, ``itertools::free`` will
 218       be removed in the next version
 219
 220   - Removed:
 221
 222     - ZipSlices, use .zip() instead
 223     - .enumerate_from(), ZipTrusted, due to being unstable
 224     - .mend_slices(), moved to crate odds
 225     - Stride, StrideMut, moved to crate odds
 226     - linspace(), moved to crate itertools-num
 227     - .sort_by(), use .sorted_by()
 228     - .is_empty_hint(), use .size_hint()
 229     - .dropn(), use .dropping()
 230     - .map_fn(), use .map()
 231     - .slice(), use .take() / .skip()
 232     - helper traits in misc
 233     - ``new`` constructors on iterator structs, use Itertools trait or free
 234       functions instead
 235     - ``itertools::size_hint`` is now private
 236
 237   - Behaviour changes:
 238
 239     - format and format_with helpers now panic if you try to format them more
 240       than once.
 241     - ``repeat_call`` is not double ended anymore
 242
 243   - New features:
 244
 245     - tuple flattening iterator is constructible with ``cons_tuples``
 246     - itertools reexports ``Either`` from the ``either`` crate. ``Either<L, R>``
 247       is an iterator when ``L, R`` are.
 248     - ``MinMaxResult`` now implements Copy and Clone
 249     - tuple_combinations supports 1-4 tuples of combinations (previously just 2)
 250
 251 - 0.4.19
 252
 253   - Add ``.minmax_by()``
 254   - Add ``itertools::free::cloned``
 255   - Add ``itertools::free::rciter``
 256   - Improve ``.step(n)`` slightly to take advantage of specialized Fuse better.
 257
 258 - 0.4.18
 259
 260   - Only changes related to the "unstable" crate feature. This feature is more
 261     or less deprecated.
 262
 263     - Use deprecated warnings when unstable is enabled. .enumerate_from() will
 264       be removed imminently since it's using a deprecated libstd trait.
 265
 266 - 0.4.17
 267
 268   - Fix bug in .kmerge() that caused it to often produce the wrong order (#134)
 269
 270 - 0.4.16
 271
 272   - Improve precision of the interleave_shortest adaptor's size hint (it is
 273     now computed exactly when possible).
 274
 275 - 0.4.15
 276
 277   - Fixup on top of the workaround in 0.4.14. A function in itertools::free was
 278     removed by mistake and now it is added back again.
 279
 280 - 0.4.14
 281
 282   - Workaround an upstream regression in a rust nightly build that broke
 283     compilation of of itertools::free::{interleave, merge}
 284
 285 - 0.4.13
 286
 287   - Add .minmax() and .minmax_by_key(), iterator methods for finding both minimum
 288     and maximum in one scan.
 289   - Add .format_default(), a simpler version of .format() (lazy formatting
 290     for iterators).
 291
 292 - 0.4.12
 293
 294   - Add .zip_eq(), an adaptor like .zip() except it ensures iterators
 295     of inequal length don't pass silently (instead it panics).
 296   - Add .fold_while(), an iterator method that is a fold that
 297     can short-circuit.
 298   - Add .partition_map(), an iterator method that can separate elements
 299     into two collections.
 300
 301 - 0.4.11
 302
 303   - Add .get() for Stride{,Mut} and .get_mut() for StrideMut
 304
 305 - 0.4.10
 306
 307   - Improve performance of .kmerge()
 308
 309 - 0.4.9
 310
 311   - Add k-ary merge adaptor .kmerge()
 312   - Fix a bug in .islice() with ranges a..b where a > b.
 313
 314 - 0.4.8
 315
 316   - Implement Clone, Debug for Linspace
 317
 318 - 0.4.7
 319
 320   - Add function diff_with() that compares two iterators
 321   - Add .combinations_n(), an n-ary combinations iterator
 322   - Add methods PutBack::with_value and PutBack::into_parts.
 323
 324 - 0.4.6
 325
 326   - Add method .sorted()
 327   - Add module ``itertools::free`` with free function variants of common
 328     iterator adaptors and methods.
 329     For example ``enumerate(iterable)``, ``rev(iterable)``, and so on.
 330
 331 - 0.4.5
 332
 333   - Add .flatten()
 334
 335 - 0.4.4
 336
 337   - Allow composing ZipSlices with itself
 338
 339 - 0.4.3
 340
 341   - Write iproduct!() as a single expression; this allows temporary values
 342     in its arguments.
 343
 344 - 0.4.2
 345
 346   - Add .fold_options()
 347   - Require Rust 1.1 or later
 348
 349 - 0.4.1
 350
 351   - Update .dropping() to take advantage of .nth()
 352
 353 - 0.4.0
 354
 355   - .merge(), .unique() and .dedup() now perform better due to not using
 356     function pointers
 357   - Add free functions enumerate() and rev()
 358   - Breaking changes:
 359
 360     - Return types of .merge() and .merge_by() renamed and changed
 361     - Method Merge::new removed
 362     - .merge_by() now takes a closure that returns bool.
 363     - Return type of .dedup() changed
 364     - Return type of .mend_slices() changed
 365     - Return type of .unique() changed
 366     - Removed function times(), struct Times: use a range instead
 367     - Removed deprecated macro icompr!()
 368     - Removed deprecated FnMap and method .fn_map(): use .map_fn()
 369     - .interleave_shortest() is no longer guaranteed to act like fused
 370
 371 - 0.3.25
 372
 373   - Rename .sort_by() to .sorted_by(). Old name is deprecated.
 374   - Fix well-formedness warnings from RFC 1214, no user visible impact
 375
 376 - 0.3.24
 377
 378   - Improve performance of .merge()'s ordering function slightly
 379
 380 - 0.3.23
 381
 382   - Added .chunks(), similar to (and based on) .group_by_lazy().
 383   - Tweak linspace to match numpy.linspace and make it double ended.
 384
 385 - 0.3.22
 386
 387   - Added ZipSlices, a fast zip for slices
 388
 389 - 0.3.21
 390
 391   - Remove `Debug` impl for `Format`, it will have different use later
 392
 393 - 0.3.20
 394
 395   - Optimize .group_by_lazy()
 396
 397 - 0.3.19
 398
 399   - Added .group_by_lazy(), a possibly nonallocating group by
 400   - Added .format(), a nonallocating formatting helper for iterators
 401   - Remove uses of RandomAccessIterator since it has been deprecated in rust.
 402
 403 - 0.3.17
 404
 405   - Added (adopted) Unfold from rust
 406
 407 - 0.3.16
 408
 409   - Added adaptors .unique(), .unique_by()
 410
 411 - 0.3.15
 412
 413   - Added method .sort_by()
 414
 415 - 0.3.14
 416
 417   - Added adaptor .while_some()
 418
 419 - 0.3.13
 420
 421   - Added adaptor .interleave_shortest()
 422   - Added adaptor .pad_using()
 423
 424 - 0.3.11
 425
 426   - Added assert_equal function
 427
 428 - 0.3.10
 429
 430   - Bugfix .combinations() size_hint.
 431
 432 - 0.3.8
 433
 434   - Added source RepeatCall
 435
 436 - 0.3.7
 437
 438   - Added adaptor PutBackN
 439   - Added adaptor .combinations()
 440
 441 - 0.3.6
 442
 443   - Added itertools::partition, partition a sequence in place based on a predicate.
 444   - Deprecate icompr!() with no replacement.
 445
 446 - 0.3.5
 447
 448   - .map_fn() replaces deprecated .fn_map().
 449
 450 - 0.3.4
 451
 452   - .take_while_ref() *by-ref adaptor*
 453   - .coalesce() *adaptor*
 454   - .mend_slices() *adaptor*
 455
 456 - 0.3.3
 457
 458   - .dropping_back() *method*
 459   - .fold1() *method*
 460   - .is_empty_hint() *method*
 461
 462 License
 463 -------
 464
 465 Dual-licensed to be compatible with the Rust project.
 466
 467 Licensed under the Apache License, Version 2.0
 468 http://www.apache.org/licenses/LICENSE-2.0 or the MIT license
 469 http://opensource.org/licenses/MIT, at your
 470 option. This file may not be copied, modified, or distributed
 471 except according to those terms.