1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
# NEWS for Ruby 3.1.0
This document is a list of user visible feature changes
since the **3.0.0** release, except for bug fixes.
Note that each entry is kept to a minimum, see links for details.
## Language changes
* Pin operator now takes an expression. [[Feature #17411]]
```ruby
Prime.each_cons(2).lazy.find_all{_1 in [n, ^(n + 2)]}.take(3).to_a
#=> [[3, 5], [5, 7], [11, 13]]
```
* Multiple assignment evaluation order has been made consistent with
single assignment evaluation order. With single assignment, Ruby
uses a left-to-right evaluation order. With this code:
```ruby
foo[0] = bar
```
The following evaluation order is used:
1. `foo`
2. `bar`
3. `[]=` called on the result of `foo`
In Ruby before 3.1.0, multiple assignment did not follow this
evaluation order. With this code:
```ruby
foo[0], bar.baz = a, b
```
Versions of Ruby before 3.1.0 would evaluate in the following
order
1. `a`
2. `b`
3. `foo`
4. `[]=` called on the result of `foo`
5. `bar`
6. `baz=` called on the result of `bar`
Starting in Ruby 3.1.0, evaluation order is now consistent with
single assignment, with the left hand side being evaluated before
the right hand side:
1. `foo`
2. `bar`
3. `a`
4. `b`
5. `[]=` called on the result of `foo`
6. `baz=` called on the result of `bar`
[[Bug #4443]]
## Command line options
## Core classes updates
Outstanding ones only.
* Array
* Array#intersect? is added. [[Feature #15198]]
* Enumerable
* Enumerable#compact is added. [[Feature #17312]]
* Enumerable#tally now accepts an optional hash to count. [[Feature #17744]]
* Enumerator::Lazy
* Enumerator::Lazy#compact is added. [[Feature #17312]]
* File
* File.dirname now accepts an optional argument for the level to
strip path components. [[Feature #12194]]
* Module
* Module#prepend now modifies the ancestor chain if the receiver
already includes the argument. Module#prepend still does not
modify the ancestor chain if the receiver has already prepended
the argument. [[Bug #17423]]
* Struct
* Passing only keyword arguments to Struct#initialize is warned.
You need to use a Hash literal to set a Hash to a first member.
[[Feature #16806]]
* Queue
* Queue#initialize now accepts an Enumerable of initial values.
[[Feature #17327]]
* Thread
* Thread#native_thread_id is added. [[Feature #17853]]
* Thread::Backtrace
* Thread::Backtrace.limit, which returns the value to limit backtrace
length set by `--backtracse-limit` command line option, is added.
[[Feature #17479]]
* $LOAD_PATH
* $LOAD_PATH.resolve_feature_path does not raise. [[Feature #16043]]
* Fiber Scheduler
* Add support for `Addrinfo.getaddrinfo` using `address_resolve` hook.
[[Feature #17370]]
* Introduce non-blocking `Timeout.timeout` using `timeout_after` hook.
[[Feature #17470]]
* IO hooks `io_wait`, `io_read`, `io_write`, receive the original IO object
where possible. [[Bug #18003]]
* Make `Monitor` fiber-safe. [[Bug #17827]]
## Stdlib updates
Outstanding ones only.
## Compatibility issues
Excluding feature bug fixes.
* `rb_io_wait_readable`, `rb_io_wait_writable` and `rb_wait_for_single_fd` are
deprecated in favour of `rb_io_maybe_wait_readable`,
`rb_io_maybe_wait_writable` and `rb_io_maybe_wait` respectively.
`rb_thread_wait_fd` and `rb_thread_fd_writable` are deprecated. [[Bug #18003]]
## Stdlib compatibility issues
* `ERB#initialize` warns `safe_level` and later arguments even without -w.
[[Feature #14256]]
## C API updates
## Implementation improvements
### JIT
* The default `--jit-max-cache` is changed from 100 to 10000.
* The JIT compiler no longer skips compilation of methods longer than
1000 instructions.
* `RubyVM::MJIT` is renamed to `RubyVM::JIT`. [[Feature #17490]]
## Static analysis
### RBS
### TypeProf
## Miscellaneous changes
* lib/objspace/trace.rb is added, which is a tool for tracing the object
allocation. Just by requiring this file, tracing is started *immediately*.
Just by `Kernel#p`, you can investigate where an object was created.
Note that just requiring this file brings a large performance overhead.
This is only for debugging purpose. Do not use this in production.
[Feature #17762]
[Bug #4443]: https://bugs.ruby-lang.org/issues/4443
[Feature #12194]: https://bugs.ruby-lang.org/issues/12194
[Feature #14256]: https://bugs.ruby-lang.org/issues/14256
[Feature #15198]: https://bugs.ruby-lang.org/issues/15198
[Feature #16043]: https://bugs.ruby-lang.org/issues/16043
[Feature #16806]: https://bugs.ruby-lang.org/issues/16806
[Feature #17312]: https://bugs.ruby-lang.org/issues/17312
[Feature #17327]: https://bugs.ruby-lang.org/issues/17327
[Feature #17411]: https://bugs.ruby-lang.org/issues/17411
[Bug #17423]: https://bugs.ruby-lang.org/issues/17423
[Feature #17479]: https://bugs.ruby-lang.org/issues/17479
[Feature #17490]: https://bugs.ruby-lang.org/issues/17490
[Feature #17744]: https://bugs.ruby-lang.org/issues/17744
[Feature #17762]: https://bugs.ruby-lang.org/issues/17762
[Bug #18003]: https://bugs.ruby-lang.org/issues/18003
[Feature #17370]: https://bugs.ruby-lang.org/issues/17370
[Feature #17470]: https://bugs.ruby-lang.org/issues/17470
[Feature #17853]: https://bugs.ruby-lang.org/issues/17853
[Bug #17827]: https://bugs.ruby-lang.org/issues/17827
|
