[#88240] [Ruby trunk Feature#14759] [PATCH] set M_ARENA_MAX for glibc malloc — sam.saffron@...
Issue #14759 has been updated by sam.saffron (Sam Saffron).
3 messages
2018/08/01
[#88251] Re: [ruby-alerts:8236] failure alert on trunk@P895 (NG (r64134)) — Eric Wong <normalperson@...>
[email protected] wrote:
3 messages
2018/08/01
[#88305] [Ruby trunk Bug#14968] [PATCH] io.c: make all pipes nonblocking by default — normalperson@...
Issue #14968 has been reported by normalperson (Eric Wong).
4 messages
2018/08/06
[#88331] [Ruby trunk Feature#13618] [PATCH] auto fiber schedule for rb_wait_for_single_fd and rb_waitpid — samuel@...
Issue #13618 has been updated by ioquatix (Samuel Williams).
3 messages
2018/08/08
[#88342] [Ruby trunk Feature#14955] [PATCH] gc.c: use MADV_FREE to release most of the heap page body — ko1@...
Issue #14955 has been updated by ko1 (Koichi Sasada).
3 messages
2018/08/08
[#88433] [Ruby trunk Feature#13618] [PATCH] auto fiber schedule for rb_wait_for_single_fd and rb_waitpid — ko1@...
SXNzdWUgIzEzNjE4IGhhcyBiZWVuIHVwZGF0ZWQgYnkga28xIChLb2ljaGkgU2FzYWRhKS4KCgpX
4 messages
2018/08/10
[#88467] Re: [Ruby trunk Feature#13618] [PATCH] auto fiber schedule for rb_wait_for_single_fd and rb_waitpid
— Eric Wong <normalperson@...>
2018/08/14
a28xQGF0ZG90Lm5ldCB3cm90ZToKPiBJc3N1ZSAjMTM2MTggaGFzIGJlZW4gdXBkYXRlZCBieSBr
[#88475] [Ruby trunk Misc#14937] [PATCH] thread_pthread: lazy-spawn timer-thread only on contention — ko1@...
Issue #14937 has been updated by ko1 (Koichi Sasada).
3 messages
2018/08/14
[#88491] Re: [ruby-cvs:71466] k0kubun:r64374 (trunk): test_function.rb: skip running test — Eric Wong <normalperson@...>
[email protected] wrote:
5 messages
2018/08/15
[#88495] Re: [ruby-cvs:71466] k0kubun:r64374 (trunk): test_function.rb: skip running test
— Takashi Kokubun <takashikkbn@...>
2018/08/15
SSBzZWUuIFBsZWFzZSByZW1vdmUgdGhlIHRlc3QgaWYgdGhlIHRlc3QgaXMgdW5uZWNlc3Nhcnku
[#88496] Re: [ruby-cvs:71466] k0kubun:r64374 (trunk): test_function.rb: skip running test
— Eric Wong <normalperson@...>
2018/08/15
Takashi Kokubun <[email protected]> wrote:
[#88523] [Ruby trunk Bug#14999] ConditionVariable doesn't reacquire the Mutex if Thread#kill-ed — eregontp@...
Issue #14999 has been updated by Eregon (Benoit Daloze).
4 messages
2018/08/17
[#88524] Re: [Ruby trunk Bug#14999] ConditionVariable doesn't reacquire the Mutex if Thread#kill-ed
— Eric Wong <normalperson@...>
2018/08/18
[email protected] wrote:
[#88549] [Ruby trunk Bug#14999] ConditionVariable doesn't reacquire the Mutex if Thread#kill-ed — eregontp@...
Issue #14999 has been updated by Eregon (Benoit Daloze).
3 messages
2018/08/19
[#88676] [Ruby trunk Misc#15014] thread.c: use rb_hrtime_scalar for high-resolution time operations — ko1@...
Issue #15014 has been updated by ko1 (Koichi Sasada).
5 messages
2018/08/27
[#88677] Re: [Ruby trunk Misc#15014] thread.c: use rb_hrtime_scalar for high-resolution time operations
— Eric Wong <normalperson@...>
2018/08/27
[email protected] wrote:
[#88678] Re: [Ruby trunk Misc#15014] thread.c: use rb_hrtime_scalar for high-resolution time operations
— Koichi Sasada <ko1@...>
2018/08/27
On 2018/08/27 16:16, Eric Wong wrote:
[#88716] Re: [ruby-dev:43715] [Ruby 1.9 - Bug #595] Fiber ignores ensure clause — Eric Wong <normalperson@...>
Koichi Sasada wrote:
4 messages
2018/08/29
[#88723] [Ruby trunk Bug#15041] [PATCH] cont.c: set th->root_fiber to current fiber at fork — ko1@...
Issue #15041 has been updated by ko1 (Koichi Sasada).
3 messages
2018/08/29
[#88767] [Ruby trunk Bug#15050] GC after forking with fibers crashes — ko1@...
Issue #15050 has been updated by ko1 (Koichi Sasada).
7 messages
2018/08/31
[#88769] Re: [Ruby trunk Bug#15050] GC after forking with fibers crashes
— Eric Wong <normalperson@...>
2018/08/31
Koichi Sasada <[email protected]> wrote:
[#88770] Re: [Ruby trunk Bug#15050] GC after forking with fibers crashes
— Koichi Sasada <ko1@...>
2018/08/31
[#88773] Re: [Ruby trunk Bug#15050] GC after forking with fibers crashes
— Eric Wong <normalperson@...>
2018/08/31
Koichi Sasada <[email protected]> wrote:
[#88774] Re: [ruby-alerts:8955] failure alert on trunk@P895 (NG (r64594)) — Eric Wong <normalperson@...>
[email protected] wrote:
3 messages
2018/08/31
[ruby-core:88694] [Ruby trunk Feature#14912] Introduce pattern matching syntax
From:
dsisnero@...
Date:
2018-08-27 18:34:30 UTC
List:
ruby-core #88694
Issue #14912 has been updated by dsisnero (Dominic Sisneros).
"The patterns are run in sequence until the first one that matches."
This means O(n) time for matching. If we are adding this with changes to compiler, we should try to compile it to hash lookup O(1) time
Does this allow nesting of patterns Do patterns compose or nest?
def simplify(n)
case n
in IntNode(n)
then n
in NegNode( Negnode n) then
simplify( NegNode.new( simplify (n) )
in AddNode(IntNode(0), right) then
simplify(right)
in MulNode(IntNode(1) right) then
simplify(right)
etc
Java is going to get pattern matching also and has some good ideas
https://www.youtube.com/watchv=n3_8YcYKScw&list=PLX8CzqL3ArzXJ2EGftrmz4SzS6NRr6p2n&index=1&t=907s
and
http://cr.openjdk.java.net/~briangoetz/amber/pattern-match.html
Their proposal includes nesting and also is O(1) time.
Not sure how much translates though.
----------------------------------------
Feature #14912: Introduce pattern matching syntax
https://bugs.ruby-lang.org/issues/14912#change-73754
* Author: ktsj (Kazuki Tsujimoto)
* Status: Open
* Priority: Normal
* Assignee:
* Target version:
----------------------------------------
I propose new pattern matching syntax.
# Pattern syntax
Here's a summary of pattern syntax.
```
# case version
case expr
in pat [if|unless cond]
...
in pat [if|unless cond]
...
else
...
end
pat: var # Variable pattern. It matches any value, and binds the variable name to that value.
| literal # Value pattern. The pattern matches an object such that pattern === object.
| Constant # Ditto.
| var_ # Ditto. It is equivalent to pin operator in Elixir.
| (pat, ..., *var, pat, ..., id:, id: pat, ..., **var) # Deconstructing pattern. See below for more details.
| pat(pat, ...) # Ditto. Syntactic sugar of (pat, pat, ...).
| pat, ... # Ditto. You can omit the parenthesis (top-level only).
| pat | pat | ... # Alternative pattern. The pattern matches if any of pats match.
| pat => var # As pattern. Bind the variable to the value if pat match.
# one-liner version
$(pat, ...) = expr # Deconstructing pattern.
```
The patterns are run in sequence until the first one that matches.
If no pattern matches and no else clause, NoMatchingPatternError exception is raised.
## Deconstructing pattern
This is similar to Extractor in Scala.
The patten matches if:
* An object have #deconstruct method
* Return value of #deconstruct method must be Array or Hash, and it matches sub patterns of this
```
class Array
alias deconstruct itself
end
case [1, 2, 3, d: 4, e: 5, f: 6]
in a, *b, c, d:, e: Integer | Float => i, **f
p a #=> 1
p b #=> [2]
p c #=> 3
p d #=> 4
p i #=> 5
p f #=> {f: 6}
e #=> NameError
end
```
This pattern can be used as one-liner version like destructuring assignment.
```
class Hash
alias deconstruct itself
end
$(x:, y: (_, z)) = {x: 0, y: [1, 2]}
p x #=> 0
p z #=> 2
```
# Sample code
```
class Struct
def deconstruct; [self] + values; end
end
A = Struct.new(:a, :b)
case A[0, 1]
in (A, 1, 1)
:not_match
in A(x, 1) # Syntactic sugar of above
p x #=> 0
end
```
```
require 'json'
$(x:, y: (_, z)) = JSON.parse('{"x": 0, "y": [1, 2]}', symbolize_names: true)
p x #=> 0
p z #=> 2
```
# Implementation
* https://github.com/k-tsj/ruby/tree/pm2.7-prototype
* Test code: https://github.com/k-tsj/ruby/blob/pm2.7-prototype/test_syntax.rb
# Design policy
* Keep compatibility
* Don't define new reserved words
* 0 conflict in parse.y. It passes test/test-all
* Be Ruby-ish
* Powerful Array, Hash support
* Encourage duck typing style
* etc
* Optimize syntax for major use case
* You can see several real use cases of pattern matching at following links :)
* https://github.com/k-tsj/power_assert/blob/8e9e0399a032936e3e3f3c1f06e0d038565f8044/lib/power_assert.rb#L106
* https://github.com/k-tsj/pattern-match/network/dependents
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