N3784: Improvements to std::future and Related APIs -- Gustafsson, Laksberg, Sutter, Mithani

By Blog Staff | Oct 18, 2013 10:49 AM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3784

Date: 2013-09-27

Improvements to std::future and Related APIs

by Niklas Gustafsson, Artur Laksberg, Herb Sutter, Sana Mithani

Excerpt:

This proposal is an evolution of the functionality of std::future/std::shared_future. It details additions which can enable wait free compositions of asynchronous operations.

This document supersedes N3634: the title has been changed, and the proposed changes have been modified to be expressed as edits to the C++ Draft Standard.

New in this version: implicit unwrapping (one level) of future<future<R>> to future<R> in then().

N3782: Index Based Ranges (Rev. 1) -- Arno Schödl, Fabio Fracassi

By Blog Staff | Oct 18, 2013 10:46 AM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3782

Date: 2013-09-24

Index Based Ranges (Rev. 1)

by Arno Schödl, Fabio Fracassi

Excerpt:

Key Points

In contrast to most currently popular range implementations, which define range iterations in terms of (pairs of) iterators we propose to use range adaptors and indices (which is similar to N1873 - Cursor/Property Maps). The most important consequence of this is that we can avoid ”Fat Iterators” when stacking range adaptors, in particular range filters.

Ranges and Traversables

This paper is intended to be fully compatible with N3763 - Traversable Arguments. We intedend to use the Traversable concept as a basis wherever applicable. N3763 sets a good foundation for making Traversables easy to work with. In this paper we would like to explore the design space beyond this basis to make working with them both easy and powerful for programmers.

N3780: Why Deprecating async() Is the Worst of All Options -- Nicolai Josuttis

By Blog Staff | Oct 18, 2013 10:42 AM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3780

Date: 2013-109-26

Why Deprecating async() Is the Worst of All Options

by Nicolai Josuttis

Note: This was an intra-meeting paper in Chicago, and std::async was not deprecated.

N3772: Changing the type of address-of-member expression -- David Rodríguez Ibeas

By Blog Staff | Oct 18, 2013 10:39 AM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3772

Date: 2013-09-05

Changing the type of address-of-member expression

by David Rodriguez Ibeas

Excerpt:

This proposal addresses the same issue as CWG closed issue 203 "Type of address-ofmember" by providing a broader view of the issue and the implications that it has on other parts of the C++ standard.

N3770: C++ CD Comment Status, Rev. 1 -- Miller, Meredith

By Blog Staff | Oct 18, 2013 10:36 AM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3770

Date: 2013-10-14

C++ CD Comment Status, Rev. 1

by William M. Miller, Alisdair Meredith

Excerpt:

This document summarizes the status of WG21 following the 2013-09 (Chicago) meeting in addressing National Body comments on Committee Draft document N3690. It does not contain the results of the Library Working Group deliberations, which have not yet been fully processed.

N3768: WG21 Minutes (September 2013), Chicago IL USA -- Kyle Kloepper

By Blog Staff | Oct 18, 2013 10:30 AM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3768

Date: 2013-10-16

Minutes (September 2013): PL22.16 Meeting No. 61, WG21 Meeting No. 56, 23-28 September 2013, Chicago, Illinois, USA

by Kyle Kloepper

C++11 and Boost

By Meeting C++ | Oct 17, 2013 10:11 AM | Tags: intermediate experimental c++11 boost advanced

What issues arise when combining C++11 and (older) Boost code that has pre-standard versions of C++11 features?

C++11 and Boost

by Jens Weller

From the article:

Some parts of the Standard Library in C++11 are predated in boost. When playing around with C++11, you get used to using some parts in the Standard Library that are used in C++03 with their boost counterpart. Also, there is some libraries now occuring, which are C++11 based, so interfacing with either boost or C++11 code is soon an issue.

N3820: Working Draft, Technical Specification -- Array Extensions -- Lawrence Crowl

By Blog Staff | Oct 16, 2013 10:31 AM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3820

Date: 2013-10-10

Working Draft, Technical Specification — Array Extensions

by Lawrence Crowl

Excerpt:

This Technical Specification specifies requirements for implementations of various extensions for arrays to the C++ language and library. Included are:

arrays of runtime bound: The core language is extended to permit run-time computation of the bound of an array with automatic  storage duration.

class dynarray: The library is extended with a class that specifies an array size only on construction.

No Runtime Overhead -- Bulldozer00

By Blog Staff | Oct 16, 2013 07:24 AM | Tags: basics

A little nugget about the free-as-in-no-overhead-ness of unique_ptr and std::move:

No Runtime Overhead

by Bulldozer00

From the article:

Unless I really need shared ownership of a dynamically allocated object, which I haven’t so far, I stick to the slimmer and more performant std::unique_ptr. ...

Out Parameters, Move Semantics, and Stateful Algorithms -- Eric Niebler

By Blog Staff | Oct 15, 2013 06:35 AM | Tags: intermediate efficiency c++11

In this article, Eric Niebler discusses an issue of API design regarding the age-old question of out parameters versus return-by-value, this time in light of move semantics. He uses std::getline as his example.

Out Parameters, Move Semantics, and Stateful Algorithms

by Eric Niebler

From the article:

I think getline is a curious example because what looks at first blush like a pure out parameter is, in fact, an in/out parameter; on the way in, getline uses the passed-in buffer’s capacity to make it more efficient. This puts getline into a large class of algorithms that work better when they have a chance to cache or precompute something.