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<!DOCTYPE html><html><head><meta charset="utf-8"><style>html { font-size: 100%; overflow-y: scroll; -webkit-text-size-adjust: 100%; -ms-text-size-adjust: 100%; }
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</style><title>N4764</title></head><body>
<h1>N4764 Editors' Report -- Programming Languages -- C++</h1>
<p>2018-07-07 <br />
Richard Smith (editor) (Google Inc) <br />
Thomas Köppe (co-editor) (Google DeepMind) <br />
Jens Maurer (co-editor) <br />
Dawn Perchik (co-editor) (Bright Side Computing, LLC) <br />
<code><[email protected]></code></p>
<h2>Acknowledgements</h2>
<p>Special thanks to Casey Carter for supplying a pull request to merge
<a href="http://wg21.link/p0898r3">P0898R3</a> (LWG motion 28),
and working with us on editorial cleanups within the
12 pages of added text.</p>
<p>Thanks to all those who have <a href="https://github.com/cplusplus/draft/wiki/How-to-submit-an-editorial-issue">submitted editorial
issues</a>
and to those who have provided pull requests with fixes.</p>
<h2>New papers</h2>
<ul>
<li><a href="http://wg21.link/n4762">N4762</a> is the current working draft for C++20. It replaces <a href="http://wg21.link/n4750">N4750</a>.</li>
<li>N4764 is this Editors' Report.</li>
</ul>
<h2>Motions incorporated into working draft</h2>
<h3>Core working group motions</h3>
<p>CWG motion 1: <a href="http://wg21.link/p1113r0">Core issue resolutions</a> for 6 issues in "ready" status applied:</p>
<ul>
<li><a href="http://wg21.link/cwg2254">2254</a> Standard-layout classes and bit-fields</li>
<li><a href="http://wg21.link/cwg2293">2293</a> Requirements for <em>simple-template-id</em> used as a <em>class-name</em></li>
<li><a href="http://wg21.link/cwg2294">2294</a> Dependent <code>auto</code> static data members</li>
<li><a href="http://wg21.link/cwg2321">2321</a> Conditional operator and cv-qualified class prvalues</li>
<li><a href="http://wg21.link/cwg2322">2322</a> Substitution failure and lexical order</li>
<li><a href="http://wg21.link/cwg2339">2339</a> Underspecified template arguments in structured bindings</li>
</ul>
<p>CWG motion 2: <a href="http://wg21.link/p1114r0">Core issue resolutions</a> for 6 issues in "tentatively ready" status applied:</p>
<ul>
<li><a href="http://wg21.link/cwg2233">2233</a> Function parameter packs following default arguments</li>
<li><a href="http://wg21.link/cwg2249">2249</a> <em>identifier</em>s and <em>id-expression</em>s</li>
<li><a href="http://wg21.link/cwg2285">2285</a> Issues with structured bindings</li>
<li><a href="http://wg21.link/cwg2351">2351</a> <code>void{}</code></li>
<li><a href="http://wg21.link/cwg2356">2356</a> Base class copy and move constructors should not be inherited</li>
<li><a href="http://wg21.link/cwg2359">2359</a> Unintended copy initialization with designated initializers <strong>(not a DR)</strong></li>
</ul>
<p>CWG motion 3: <a href="http://wg21.link/p0806r2">P0806R2 "Deprecate implicit capture of <code>this</code> via <code>[=]</code>"</a></p>
<p>CWG motion 4: <a href="http://wg21.link/p1042r1">P1042R1 "<code>__VA_OPT__</code> wording clarifications"</a></p>
<p>CWG motion 5: <a href="http://wg21.link/p0929r2">P0929R2 "Checking for abstract class types"</a> applied, resolving 2 core issues:</p>
<ul>
<li><a href="http://wg21.link/cwg1640">1640</a> Array of abstract instance of class template</li>
<li><a href="http://wg21.link/cwg1646">1646</a> <em>decltype-specifier</em>s, abstract classes, and deduction failure</li>
</ul>
<p>CWG motion 6: <a href="http://wg21.link/p0732r2">P0732R2 "Class types in non-type template parameters"</a></p>
<p>CWG motion 7 was not approved</p>
<p>CWG motion 8: <a href="http://wg21.link/p1025r1">P1025R1 "Update the reference to the Unicode standard"</a></p>
<p>CWG motion 9: <a href="http://wg21.link/p0528r3">P0528R3 "The curious case of padding bits, featuring atomic compare-and-exchange"</a></p>
<p>CWG motion 10: <a href="http://wg21.link/p0722r3">P0722R3 "Efficient sized delete for variable sized classes"</a></p>
<p>CWG motion 11: <a href="http://wg21.link/p1064r0">P1064R0 "Allowing virtual function calls in constant expressions"</a></p>
<p>CWG motion 12: <a href="http://wg21.link/p1008r1">P1008R1 "Prohibit aggregates with user-declared constructors"</a></p>
<p>CWG motion 13: <a href="http://wg21.link/p1120r0">P1120R0 "Consistency improvements for <code><=></code> and other comparison operators"</a></p>
<p>CWG motion 14: <a href="http://wg21.link/p0542r5">P0542R5 "Contract-based programming"</a> <strong>see below</strong></p>
<p>CWG motion 15: <a href="http://wg21.link/p0941r2">P0941R2 "Feature-test macros"</a> <strong>see below</strong></p>
<p>CWG motion 16: <a href="http://wg21.link/p0892r2">P0892R2 "<code>explicit(bool)</code>"</a></p>
<h3>Library working group motions</h3>
<p>LWG motions 1-5 apply to the Parallelism TS</p>
<p>LWG motions 6 and 7 apply to the Reflection TS</p>
<p>LWG motions 8 and 9 apply to the Coroutines TS</p>
<p>LWG motion 10 applies to the Networking TS</p>
<p>LWG motion 11: <a href="http://wg21.link/p1082r0">Library issue resolutions</a> for 14 issues in "Ready" and "Tentatively Ready" status applied:</p>
<ul>
<li><a href="http://wg21.link/lwg2139">2139</a> What is a user-defined type? <strong>see below</strong></li>
<li><a href="http://wg21.link/lwg2970">2970</a> Return type of <code>std::visit</code> misspecified</li>
<li><a href="http://wg21.link/lwg3058">3058</a> Parallel <code>adjacent_difference</code> shouldn't require creating temporaries</li>
<li><a href="http://wg21.link/lwg3062">3062</a> Unnecessary <code>decay_t</code> in <code>is_execution_policy_v</code> should be <code>remove_cvref_t</code></li>
<li><a href="http://wg21.link/lwg3067">3067</a> <code>recursive_directory_iterator::pop</code> must invalidate</li>
<li><a href="http://wg21.link/lwg3074">3074</a> Non-member functions for <code>valarray</code> should only deduce from the <code>valarray</code></li>
<li><a href="http://wg21.link/lwg3076">3076</a> <code>basic_string</code> CTAD ambiguity</li>
<li><a href="http://wg21.link/lwg3079">3079</a> <a href="http://wg21.link/lwg2935">LWG 2935</a> forgot to fix the <code>existing_p</code> overloads of <code>create_directory</code></li>
<li><a href="http://wg21.link/lwg3080">3080</a> Floating point <code>from_chars</code> pattern specification breaks round-tripping</li>
<li><a href="http://wg21.link/lwg3083">3083</a> What should <code>ios::iword(-1)</code> do?</li>
<li><a href="http://wg21.link/lwg3094">3094</a> [time.duration.io]p4 makes surprising claims about encoding</li>
<li><a href="http://wg21.link/lwg3100">3100</a> Unnecessary and confusing "empty span" wording</li>
<li><a href="http://wg21.link/lwg3102">3102</a> Clarify <code>span</code> <code>iterator</code> and <code>const_iterator</code> behavior</li>
<li><a href="http://wg21.link/lwg3104">3104</a> Fixing <code>duration</code> division</li>
<li>Resolution of <a href="http://wg21.link/lwg3071">3071</a> (<code>read_until</code> still refers to
"input sequence") from P1082R0 was not part of this motion, as it applies to
the Networking TS.</li>
</ul>
<p>LWG motion 12: <a href="http://wg21.link/p0475r1">Library issue resolution</a> for 1 issue applied:</p>
<ul>
<li><a href="http://wg21.link/lwg2511">2511</a> Guaranteed copy elision for piecewise construction</li>
</ul>
<p>LWG motion 13: <a href="http://wg21.link/p0476r2">P0476R2 "Bit-casting object representations"</a></p>
<p>LWG motion 14: <a href="http://wg21.link/p0788r3">P0788R3 "Standard library specification in a concepts and contracts world"</a></p>
<p>LWG motion 15 was not approved</p>
<p>LWG motion 16: <a href="http://wg21.link/p0458r2">P0458R2 "Checking for existence of an element in associative containers"</a></p>
<p>LWG motion 17: <a href="http://wg21.link/p0759r1">P0759R1 "<code>fpos</code> requirements"</a></p>
<p>LWG motion 18: <a href="http://wg21.link/p1023r0">P1023R0 "<code>constexpr</code> comparison operators for <code>std::array</code>"</a></p>
<p>LWG motion 19: <a href="http://wg21.link/p0769r2">P0769R2 "Add <code>shift</code> to <code><algorithm></code>"</a></p>
<p>LWG motion 20: <a href="http://wg21.link/p0887r1">P0887R1 "The <code>identity</code> metafunction"</a></p>
<p>LWG motion 21: <a href="http://wg21.link/p0879r0">P0879R0 "<code>constexpr</code> for <code>swap</code> and <code>swap</code>-related functions"</a> applied, resolving 1 issue:</p>
<ul>
<li><a href="http://wg21.link/lwg2800">2800</a> <code>constexpr</code> <code>swap</code></li>
</ul>
<p>LWG motion 22: <a href="http://wg21.link/p0758r1">P0758R1 "Implicit conversion traits and utility functions"</a></p>
<p>LWG motion 23: <a href="http://wg21.link/p0556r3">P0556R3 "Integral power-of-2 operations"</a></p>
<p>LWG motion 24: <a href="http://wg21.link/p0019r8">P0019R8 "<code>atomic_ref</code>"</a></p>
<p>LWG motion 25: <a href="http://wg21.link/p0935r0">P0935R0 "Eradicating unnecessarily explicit default constructors from the standard library"</a></p>
<p>LWG motion 26: <a href="http://wg21.link/p0646r1">P0646R1 "Improving the return value of <code>erase</code>-like algorithms"</a></p>
<p>LWG motion 27: <a href="http://wg21.link/p0619r4">P0619R4 "Reviewing deprecated facilities of C++17 for C++20"</a> <strong>see below</strong></p>
<p>LWG motion 28: <a href="http://wg21.link/p0898r3">P0898R3 "Standard library concepts"</a> <strong>see below</strong></p>
<h2>Notable editorial changes</h2>
<h3>CWG motion 14</h3>
<p>Subclause structure and paragraph order of [dcl.attr.contracts] was reworked.
Several normatively-redundant statements were converted to notes or removed.</p>
<h3>CWG motion 15</h3>
<p>Multiple papers moved at this meeting included suggested feature-test macros.
However, these were not presented as editing instructions, because we did not
have feature-test macros in the standard wording yet. After consultation with
CWG and LWG, the following feature test macros have been added in addition to
those listed in CWG motion 15 (all with value <code>201806L</code>):</p>
<ul>
<li><code>__has_cpp_attribute(assert)</code></li>
<li><code>__has_cpp_attribute(ensures)</code></li>
<li><code>__has_cpp_attribute(expects)</code></li>
<li><code>__cpp_explicit_bool</code></li>
<li><code>__cpp_nontype_template_parameter_class</code></li>
<li><code>__cpp_lib_atomic_ref</code></li>
<li><code>__cpp_lib_bit_cast</code></li>
<li><code>__cpp_lib_concepts</code></li>
<li><code>__cpp_lib_constexpr_swap_algorithms</code></li>
<li><code>__cpp_lib_list_remove_return_type</code></li>
</ul>
<h3>CWG motions 16 and 12</h3>
<p>CWG motion 16 would have us change wording that was deleted by CWG motion 12.
The requested change in CWG motion 16 (from teletype "<code>explicit</code>" to body font "explicit")
was ignored.</p>
<h3>LWG motion 11: issue 2139</h3>
<p>The underlying text has changed between the drafting of the resolution to this
issue and its application. We believe every requested edit has been applied;
however, an additional use of "user-defined type" has been added to
[namespace.std] that should likely also have been covered by this wording.
It has <em>not</em> been changed.</p>
<h3>LWG motions 13 and 23</h3>
<p>These motions both introduce a <code><bit></code> header, but the organizational structure
suggested by motion 23 doesn't make sense for the functionality
added by motion 13.
The wording of motion 23 has been rearranged to fit into
the structure established by motion 13.</p>
<h3>LWG motions 16</h3>
<p>Added the new <code>contains</code> member function for associative containers to the list
of member function templates that do not participate in overload resolution
unless the comparator is transparent, after consultation with LWG.</p>
<h3>LWG motions 19 and 21</h3>
<p>LWG motion 19 adds a <code>shift_right</code> algorithm to <code><algorithm></code>
as a non-<code>constexpr</code> function template.</p>
<p>LWG motion 21 instructs that we mark
all non-parallel algorithms in <code><algorithm></code>
as <code>constexpr</code>.
Naturally, however,
its proposed wording change does not list the <code>shift_right</code> algorithm.
After consultation with LWG, <code>shift_right</code> has been marked <code>constexpr</code>
to satisfy the intent of LWG motion 21.</p>
<h3>LWG motion 27</h3>
<p>Synopses for
<code><ccomplex></code>,
<code><cstdalign></code>,
<code><cstdbool></code>, and
<code><ctgmath></code>
were not removed;
instead, they have been repurposed as synopses for
<code><complex.h></code>,
<code><stdalign.h></code>,
<code><stdbool.h></code>, and
<code><tgmath.h></code>.
(The latter used to be defined in terms of the former,
but can no longer be specified in that way.)
Also introduced a synopsis for <code><iso646.h></code>.</p>
<h3>LWG motion 28</h3>
<p>Clause labels shortened and simplified throughout.</p>
<p>The single-item clauses [concept.movable], [concept.copyable],
[concept.semiregular], and [concept.regular] have been merged into their
parent, [concepts.object].</p>
<p>The single-item clauses [concept.signed.int] and [concept.unsigned.int]
have been merged into their parent, [concept.integral].</p>
<p>Legacy concept names changed from <em>Cpp98Something</em> to <em>Cpp17Something</em>. Many of
these concepts did not exist in C++98 (which in any case was revoked and
replaced by C++03).</p>
<p>Reworked "uniform random bit generator" requirements to describe them in terms
of the <code>UniformRandomBitGenerator</code> concept.</p>
<p>Removed "there need be no subsumption relationship" wording that is already
implied by the core language rules for concepts.</p>
<h3>Editorial paper <a href="http://wg21.likn/p1076r1">P1076R1 "Clause reorganization"</a></h3>
<p>The claue reorganization described in P1076R1 and discussed at the WG21
Rapperswil meeting has been applied to the working draft, with the following
modifications:</p>
<p>[class.copy] was left containing only two paragraphs of text, neither of which
had any normative impact. It has been removed.</p>
<p>The top-level subclauses of [algorithms] have been reordered to make the
description of the <code><numeric></code> header fit better into its structure.</p>
<p>Several paragraphs of [class] describing various properties of classes have
been moved into a new subclause [class.prop] "Properties of clases".</p>
<h3>Removal of single-item subclauses</h3>
<p>The single-item subclauses
[move.iter.op=] and
[move.iter.op.const]
have been merged into [move.iter.cons].</p>
<p>The single-item subclauses
[move.iter.op.star],
[move.iter.op.ref], and
[move.iter.op.index]
have been merged into [move.iter.elem].</p>
<p>The single-item subclauses
[move.iter.op.+],
[move.iter.op.-],
[move.iter.op.incr],
[move.iter.op.+=],
[move.iter.op.decr], and
[move.iter.op.-=]
have been merged into [move.iter.nav].</p>
<p>The now-empty [move.iter.ops] has been removed.</p>
<h2>Minor editorial fixes</h2>
<p>A log of editorial fixes made to the working draft since N4750 is below.
This list excludes changes
that do not affect the body text or only affect whitespace or typeface. For a
complete list including such changes (or for the actual deltas applied by these
changes), consult the <a href="https://github.com/cplusplus/draft/compare/n4750...n4762">draft sources on github</a>.</p>
<pre><code>commit afe115acc28e33e48e2ece9f850820d6faa51757
Author: Jens Maurer <[email protected]>
Date: Fri Jul 6 10:47:19 2018 +0200
[class] Introduce a subheading 'Properties of classes'.
commit d3f80a4a994a66cc8148a6031d29182aad4f16f6
Author: Jens Maurer <[email protected]>
Date: Sat Jul 7 00:49:56 2018 +0200
[namespace.udecl] Demote normative duplication to notes (#1976)
The effects of using-declarations naming member functions
are discussed in other parts of the standard.
The effects of initializing with an inherited constructor are
discussed elsewhere, too.
commit 9459c137f138f903d670e6689b3963f0a3f7d083
Author: Jens Maurer <[email protected]>
Date: Fri Jul 6 10:40:09 2018 +0200
[time.point,time.duration] Remove class name repeated in subheadings (#2249)
commit 56c599f71e8a9cfe77233e5dcd77ccfe72d81af8
Author: Richard Smith <[email protected]>
Date: Thu Jul 5 20:22:47 2018 -0700
[algorithm.syn] Reorder after [algorithms.requirements] and
[algorithms.parallel], which apply to both <algorithm> and <numeric>.
commit 8806777151719da531aae976c46f98c485bf0580
Author: Jens Maurer <[email protected]>
Date: Wed Jul 4 08:39:53 2018 +0200
[algorithms] Integrate requirements from [numeric.ops].
commit e8d3d7029c5be1494016bc03e0004d0e9eeaa8cd
Author: Jens Maurer <[email protected]>
Date: Wed Jul 4 08:25:30 2018 +0200
Remove [class.copy] and adjust cross-references pointing there.
The normative statements that used to be contained in
[class.copy] were redundant with [dcl.init] and [over.ass].
commit 006fb15de62c93b6e3de3d32648f276c9ec70181
Author: Jens Maurer <[email protected]>
Date: Wed Jul 4 00:29:28 2018 +0200
[class.derived,class.access,special] Move into [class], as appropriate.
P1076R1: Editorial clause reorganization
commit 3c580cd204fde95a21de1830ace75d14d429f845
Author: Jens Maurer <[email protected]>
Date: Wed Jul 4 00:07:05 2018 +0200
[dcl.decl] Move into [dcl.dcl] as appropriate.
P1076R1: Editorial clause reorganization
commit 40907944b775e4da980b69565dcbaa4bd494d347
Author: Jens Maurer <[email protected]>
Date: Wed Jul 4 00:00:51 2018 +0200
[namespace.udecl] Move one level up
P1076R1: Editorial clause reorganization
commit f87c7fd1d9a258d043b7b22fb13ce6bdf6931a28
Author: Jens Maurer <[email protected]>
Date: Tue Jul 3 23:54:36 2018 +0200
[numeric.ops] Move into [algorithms], after [alg.sorting]
P1076R1: Editorial clause reorganization
commit 40719643c5f237aecf0136a001cce1d85ceaaf59
Author: Jens Maurer <[email protected]>
Date: Tue Jul 3 23:48:00 2018 +0200
[localization] Move to before [input.output]
P1076R1: Editorial clause reorganization
commit a41eef0a98e9727ca85ff12c99b27209969a62b8
Author: Jens Maurer <[email protected]>
Date: Tue Jul 3 23:37:46 2018 +0200
[time.general] Add summary table
commit 63603768789149c9b46bac7e810ddfb618e8eefe
Author: Jens Maurer <[email protected]>
Date: Tue Jul 3 23:30:45 2018 +0200
[time] Promote to a top-level clause.
P1076R1: Editorial clause reorganization
commit 006a9380cfe9e00bcee9b03884b3b4bf57bf6fa2
Author: Jens Maurer <[email protected]>
Date: Tue Jul 3 23:22:05 2018 +0200
[conv] Move as a subclause into [expr], immediately before [expr.arith.conv]
P1076R1: Editorial clause reorganization
commit 70adb738f6edbc0697d1f26c72040d6b3a971421
Author: Hubert Tong <[email protected]>
Date: Thu Jul 5 16:22:22 2018 -0400
[intro.defs] Use https in hyperlink URL; see Directives, Part 2:2018 (#2248)
commit 3fe46c716367d6e367b4c5acff344bce3f2a5cd2
Author: Jonathan Wakely <[email protected]>
Date: Fri May 11 11:53:45 2018 +0100
[class] Reformat paragraph defining standard-layout class
Move the note before the definition of M(X).
Use a nested list for the definition of M(X).
Move the example to a new paragraph.
commit 0cac48775c1b1db4038cc0e456ccef81d5dd5fdc
Author: timsong-cpp <[email protected]>
Date: Mon Jul 2 17:13:53 2018 -0400
[concepts.{lang,compare,callable}.general] Replace "section" with "subclause".
commit 9db2f62e966224e8e749913871771dd4ac886c78
Author: Jens Maurer <[email protected]>
Date: Fri Jun 15 09:08:21 2018 +0200
[basic.start,except] Harmonize references to std::terminate
commit 3846e6ba6592099145655420e3b88c6c874cd5fc
Author: Jens Maurer <[email protected]>
Date: Fri Jun 1 10:05:58 2018 +0200
[over.match.viable] Fix cross-reference to satisfaction of constraints
commit 61e272c36350786e8b3fa1662efb0a8b9484cdd5
Author: Jens Maurer <[email protected]>
Date: Thu Jun 14 11:08:25 2018 +0200
[dcl.init.ref] Avoid use of 'underlying type' for references
commit c56870954b48305df89133a80e6ab8a21a0a90e9
Author: Johel Ernesto Guerrero Peña <[email protected]>
Date: Mon Jul 2 17:10:38 2018 -0400
[temp.constr.constr], [iterator.requirements.general], [re.results.size] Replace "section" with "subclause"
commit f3b625826ae894613c9ec47bd4e1874fc46e71d4
Author: timsong-cpp <[email protected]>
Date: Mon Jul 2 17:05:50 2018 -0400
[concepts.object] Dissolve single-item subclauses. (#2240)
The following subclause headings have been removed:
[concept.movable]
[concept.copyable]
[concept.semiregular]
[concept.regular]
The content for these former subclauses now resides in the parent subclause, [concepts.object].
commit 75c9148c3d810a825765aef9f04f9689f678f7bf
Author: Johel Ernesto Guerrero Peña <[email protected]>
Date: Sat Jun 16 15:57:32 2018 -0400
[re.general] Refer to table as done in the other clauses
commit 2fdaf88fcffd65ea2ccc4e032e288c74ac94bb7d
Author: Richard Smith <[email protected]>
Date: Mon Jul 2 11:52:45 2018 -0700
[basic.lookup.unqual] Finesse "class definition" footnote to avoid
saying that a class definition is one of two components of the
definition of a class.
commit 4d757ab4026f2b1af37ea1f3c6fb8fbd4c83f0dc
Author: Jens Maurer <[email protected]>
Date: Sat Jun 30 00:23:57 2018 +0200
[class.mem] Define complete-class context
and use it, instead of having separate redundant lists
in [basic.scope.class] and [basic.lookup.unqual].
commit ade8b020efbfa8fd220d1ed7f230850f2849d593
Author: S. B. Tam <[email protected]>
Date: Tue Jul 3 02:32:45 2018 +0800
[expr.prim.id.{un,}qual] A structured binding name is an lvalue (#2234)
Fix wording here to match corresponding wording in [dcl.struct.bind].
commit 809a034ac0428dc71d3b07bb15c39a1131d2e3f8
Author: Michael Adams <[email protected]>
Date: Mon Jul 2 11:30:48 2018 -0700
[class.copy.elision] Fix typo that accidentally makes example ill-formed
commit 61b25c662399e7ebd126ee6771126aa29fed407e
Author: timsong-cpp <[email protected]>
Date: Sat Jun 30 05:27:09 2018 -0400
[{i,o}{string,f}stream.cons] Remove unmatched parenthesis (#2233)
commit 0420f57904322da8adc32890687dc914d5c06edc
Author: Jens Maurer <[email protected]>
Date: Tue Jun 19 11:23:54 2018 +0200
[dcl.attr.contract] Introduce subheadings and reorder paragraphs to fit
commit 492e6a79cd4b36488c248771b73b46ba54ec27a6
Author: Johel Ernesto Guerrero Peña <[email protected]>
Date: Wed Jun 27 21:18:27 2018 -0400
[variant.get] Consistently place comma after "otherwise"
commit 5326a0d1311682568eccd19b1f8c2512091a2a53
Author: Jens Maurer <[email protected]>
Date: Thu Jun 28 12:42:25 2018 +0200
[input.iterators,fs.rec.dir.itr.members] Disambiguate phrasing for previous value of iterators
commit 2f5d2cbcd69c0cb63bad481f44d32082dd68ea6c
Author: Jens Maurer <[email protected]>
Date: Thu Jun 28 23:54:24 2018 +0200
[depr.locale.stdcvt.req] Add normative references for encoding forms
commit 69d7e1ffeed2187c1986f727882e65890c6dfa0f
Author: Jens Maurer <[email protected]>
Date: Fri Jun 29 00:08:44 2018 +0200
[optional] Move requirements from header synopsis to class template
commit 6116910802836c517ecde9237b6ffabcdafc26cf
Author: Jens Maurer <[email protected]>
Date: Fri Jun 29 00:15:09 2018 +0200
[basic.fundamental] Add definition of 'fundamental type'
commit b65061ee7d81079e72b2467ac9307ba9a24aaf00
Author: Jens Maurer <[email protected]>
Date: Fri Jun 29 13:41:11 2018 +0200
[expr.prim.lambda,depr.capture.this] Replace 'lambda expression'
with the grammar term 'lambda-expression'.
Also remove the unused definition of 'local lambda expression'.
commit 354fa005c1b8ad55ddd1bca31bf4f8bef67db46e
Author: Jens Maurer <[email protected]>
Date: Fri May 25 10:37:36 2018 +0200
[dcl.init,over.match.ctor] Clarify copy-initialization for empty arguments.
Also turn the enumeration of direct-initialization cases into
a bulleted list, referring to grammar non-terminals.
commit 69259f9d29a571233908c4f9be5afc9b98e9a2e3
Author: Jens Maurer <[email protected]>
Date: Fri May 25 01:14:17 2018 +0200
Drop redundant 'expression'
when calling out a value category.
commit 09f1354234154602dee9a0afc12f0b160bf455ea
Author: Richard Smith <[email protected]>
Date: Fri Jun 29 13:59:12 2018 -0700
[dcl.attr.contract] Fix mention of odr-use of a parameter value to talk
about odr-use of the parameter instead; values can't be odr-used.
As agreed on the core reflector.
commit 45fa09c5e38057571284c3eda52aa479afa0f3cb
Author: Jens Maurer <[email protected]>
Date: Fri Jun 29 17:38:17 2018 +0200
[temp.dep] Fix typo 'An expressions...' (#2181)
commit 50a00f2776122a1328d29332f45e3ec20ee6d0fb
Author: Jens Maurer <[email protected]>
Date: Fri Jun 29 00:53:00 2018 +0200
[lex] Cite ISO/IEC 10646 correctly (#2226)
commit 6f6a5dd6de12968f447940049d7fbf447e0ccf9f
Author: Jens Maurer <[email protected]>
Date: Tue May 8 13:29:32 2018 +0200
[atomics.types.operations] Avoid inappropriate use of 'underlying type'
commit 35e17ec6e2f702be4c31fd99c058404223a865da
Author: Casey Carter <[email protected]>
Date: Thu Jun 28 12:28:20 2018 -0700
[algorithm.syn] Relocate the "partitions" algorithms (#2219)
Move the synopsis for the "partitions" algorithms between the "binary_search" family and the "merge" family, to agree with the order of the detailed specifications as reordered by #1245.
commit 03e97ca6af73a842d38d40977a2630b0c978eade
Author: Jens Maurer <[email protected]>
Date: Thu Apr 19 23:12:20 2018 +0200
[temp.arg.explicit,temp.mem] Clarify note about explicit template arguments
for conversion function templates and constructor templates.
commit cdad8c27d822e5aec90b86a6e72e6f093d204924
Author: Jens Maurer <[email protected]>
Date: Tue Apr 3 23:33:29 2018 +0200
[move.iterators] Dissolve single-item subclauses.
commit 1f9524d9b2a2ec95e7b48ec82ff9782e2b79d413
Author: Thomas Köppe <[email protected]>
Date: Wed Jun 27 22:42:53 2018 +0100
[support.limits.general] Fix typo: '<forwardlist>' should be '<forward_list>'
commit e0d78d373e975ccbc7cd59d5b7292c48f920b959
Author: Alisdair Meredith <[email protected]>
Date: Wed Jun 27 17:33:20 2018 -0400
[span.overview] Fix reverse_iterator for span (#2112)
There is a common convention to omit 'std::' when not strictly needed,
other than for 'std::move' and 'std::forward'. A third case is for
'reverse_iterator' and 'const_reverse_iterator' type aliases inside a
class definition, as the leading 'reverse_iterator' type alias hides
the 'std' version from the 'const_reverse_iterator' definition, and
subsequently fails to compile. This patch restore the class definition
to a safely copy/pastable state.
An additional review indicated this convention has been applied correctly
for every othert potential occurrence in the library.
commit 33e8e2b3c5c2ae9e53ed656f7e3dfe874e55ede3
Author: Casey Carter <[email protected]>
Date: Wed Jun 27 14:32:34 2018 -0700
[output.iterators] Strike useless sentence from note (#2083)
There's no such thing as an "insert pointer," and the rest of this sentence isn't much better.
commit fe3f46b976c8c19336f0007625fe3e487827ca55
Author: Arthur O'Dwyer <[email protected]>
Date: Wed Jun 27 12:12:45 2018 -0700
Harmonize phrasings of "this destructor is trivial". (#2191)
Inspired by P0602 https://lichray.github.io/trivially_variant.html
Zhihao suggested that we harmonize "trivially destructible"
wording across the rest of the Standard.
commit 14809d0b4b27395ea407734d00d0f6dc9c7b0c05
Author: Jens Maurer <[email protected]>
Date: Wed Jun 27 21:04:50 2018 +0200
[expr.spaceship] Fix typo for std::strong_equality::nonequal (#2216)
commit 2954bfccb653504279f101cf1d8c7f9fb96947ff
Author: Sergey Zubkov <[email protected]>
Date: Wed Jun 27 15:03:49 2018 -0400
[diff.cpp17.depr] Fix typo from P0619R4 (#2217)
In the paper, "raw_memory_iterator" was meant to say "raw_storage_iterator".
commit 264839261e3d0b0cb66415f2c1755d1f84d2cb3d
Author: timsong-cpp <[email protected]>
Date: Wed Jun 27 06:51:41 2018 -0400
[istreambuf.iterator.proxy] correct title and remove default template argument (#2078)
This is a class, not a class template. Also, the default template argument is 1) redundant and 2) ill-formed for violating [temp.param]p12.
commit e6794e6f167db93a519564d5fc986309d194e140
Author: Jens Maurer <[email protected]>
Date: Wed Jun 27 12:49:39 2018 +0200
[syserr] Remove class name repeated in subheadings (#2093)
commit f0e7cdd3392e91b427764abf1c9c30058a457143
Author: Jens Maurer <[email protected]>
Date: Wed Jun 27 12:49:12 2018 +0200
[smartptr] Remove class name repeated in subheadings (#2092)
commit a92cdcb6ca8aa43e49a54d22f8760e9ca9cbaad7
Author: Jens Maurer <[email protected]>
Date: Wed Jun 27 12:48:03 2018 +0200
[vector.cons] vector(const Allocator&) should be noexcept (#2182)
This fixes an oversight in the wording of
"N4258: Cleaning‐up noexcept in the Library",
which updated the overview, but not the description.
commit f4a6f328137fa59bf3aa319eb4ccb743b2205dfc
Author: Richard Smith <[email protected]>
Date: Tue Jun 26 19:06:44 2018 -0700
[alg.sorting] Fix grammar.
commit de4ddf0a8fa164c7b451b6bb500c492681a7738c
Author: Richard Smith <[email protected]>
Date: Tue Jun 26 20:00:54 2018 -0700
[cpp.cond], [cpp.predefined], [support.limits.general] Add feature-test
macros from 2018-06 motions:
__has_cpp_attribute(assert)
__has_cpp_attribute(ensures)
__has_cpp_attribute(expects)
__cpp_explicit_bool
__cpp_nontype_template_parameter_class
__cpp_lib_atomic_ref
__cpp_lib_bit_cast
__cpp_lib_concepts
__cpp_lib_constexpr_swap_algorithms
__cpp_lib_list_remove_return_type
... all with value 201806L.
commit 1984951deba6caeb117300b198e349b0e9bf841c
Author: Richard Smith <[email protected]>
Date: Tue Jun 26 18:24:56 2018 -0700
[meta.type.trans] Strike redundant and confusing note on type member of
basic_common_reference, and replace it with a clarifying description of
the primary template.
commit a5a086fada4312ee1794a5d2cb65a7ce5ac284d4
Author: Richard Smith <[email protected]>
Date: Tue Jun 26 17:51:24 2018 -0700
[meta.trans.other] Replace "(possibly cv) void" with just "cv void".
These two formulations mean the same thing.
commit cc393db472ef7e89fa4e8bc8bcce6e44979efd5e
Author: Richard Smith <[email protected]>
Date: Tue Jun 26 17:43:51 2018 -0700
[concept.strictweakorder] Fix grammar in note.
commit 01f681dd376ec6285fae0253d21745999fd9557f
Author: Richard Smith <[email protected]>
Date: Tue Jun 26 14:50:39 2018 -0700
[concept.equalitycomparable] Remove note that the equality-preserving
nature of == implies that == is reflexive. This turns out to not quite
be justified by the normative rules.
commit fbc2eef266332b8dea52718640ceca7cde9d6c1f
Author: Richard Smith <[email protected]>
Date: Mon Jun 25 18:25:06 2018 -0700
[concept.boolean] Reword satisfaction rules for Boolean to make them not
appear to depend on the "given" lvalues b1 and b2.
commit d324da9c1ea4702dfb2d595390114d872f29089e
Author: Richard Smith <[email protected]>
Date: Mon Jun 25 18:15:28 2018 -0700
[concept.destructible] Fix meaningless phrase "potentially-throwing,
even if non-throwing".
By definition, non-throwing is the opposite of potentially-throwing for
an exception-specification ([except.spec]p1).
commit 4ac1f96f51c998846ce97e81c793484a52318357
Author: Richard Smith <[email protected]>
Date: Mon Jun 25 17:34:27 2018 -0700
[concepts.equality] Add missing paragraph numbers, reorder implicit
expression variations in example for clarity and to fix overfull hbox.
commit 60ae4bf7daae6802fefef5a5f32c1d2248a51334
Author: Casey Carter <[email protected]>
Date: Fri Jun 22 20:28:23 2018 -0700
[concepts] There need be no "there need be no subsumption relationship"
... the core language rules already imply it.
commit 11b6f1844a7b43a232d55442f4af7f9ce20faa45
Author: Casey Carter <[email protected]>
Date: Fri Jun 22 21:14:00 2018 -0700
[structure.requirements] Add paragraph explaining the typographical convention for requirement names
commit bfaea046b5176152a86514a886a5b7ab66e4dffe
Author: Casey Carter <[email protected]>
Date: Wed Jun 20 09:39:06 2018 -0700
[rand.req.urng] Rework URBG requirements for clarity and simplicitly
... by removing the redundance between the new concept and the "old" requirements.
Also fixup the reference in [rand.req.eng] to properly refer [rand.req.urng] instead of the requirements table. The table has been removed, and the reference should have been to the subclause in the first place to clearly incorporate the requirements outside of the table.
commit def89125ccf441d2178e6159d6b9448f17045f6a
Author: Casey Carter <[email protected]>
Date: Wed Jun 20 11:21:43 2018 -0700
[meta.trans.other] Remove basic_common_reference requirement with no normative effect.
We already say that only T and U can be specialized. We do not need to
also say that TQual and UQual cannot be. Also clarify that users may
*partially* specialize basic_common_reference.
commit 528d382ca9b350c3aece9a57e23a2560b7ba0651
Author: Casey Carter <[email protected]>
Date: Tue Jun 19 16:31:00 2018 -0700
[meta.trans.other] Make style of common_type and common_reference consistent
...by tagging the specification of common_reference with "Note C" and basic_common_reference "Note D".
Also remove the allowance to specialize basic_common_reference "if at least one template parameter in the specialization depends on a program-defined type"; it's redundant with "...pursuant to [namespace.std]". (This is consistent with `common_type`'s wording.)
commit 2aa8b236c8afe09272fba8d0767fbc6552b301b5
Author: Casey Carter <[email protected]>
Date: Tue Jun 19 16:06:03 2018 -0700
[structure.requirements] Rephrase para 8 for clarity
commit d9c710c4f13c95d65f96d503bd45f11628fdf68a
Author: Casey Carter <[email protected]>
Date: Mon Jun 18 06:55:44 2018 -0700
[concepts.general][library.general] Concepts constrain template arguments, not parameters
commit a818d5bfb084da10818b830d210d8bb4312912e4
Author: Casey Carter <[email protected]>
Date: Thu Jun 21 09:38:44 2018 -0700
[concepts.swappable] Correct example
commit db9aee9ca04a192f32cd630cf3682d30c62a0bf7
Author: Casey Carter <[email protected]>
Date: Tue Jun 19 15:34:43 2018 -0700
[customization.point.object][meta.trans.other] Replace "user-defined" added by P0898R3 with "program-defined"
...to be consistent with the intent of LWG2139
commit 03f3764a071dfe30ef1137435a88ea036ca65c1f
Author: Casey Carter <[email protected]>
Date: Wed Jun 20 15:16:51 2018 -0700
[definitions] Redefine expression-equivalent per ISO directives