Monday, August 25, 2014

Upcoming Appearances: 2 Continents, 5 Countries, 8 Cities, Several Topics

Now that work on Effective Modern C++ is approaching completion, it's time to get out and see the world...and give technical presentations. Between September and December, I'll be giving talks in the United States, Germany, England, Poland, and Latvia. Geographically, the European presentations work out this way:
In the USA, I'll be in Bellevue, WA, Cambridge, MA, and Bala Cynwyd, PA.

The topics I'll be addressing are rather varied, including a lot of information about C++11 and C++14, the importance of CPU caches for software performance, general advice on interface design, plus some reflections on thinking about and writing "Effective" books.

You'll find details on all my upcoming presentations at my Upcoming Talks page, e.g., exact dates, locations, and topics. I think all the presentations will be fun, but let me call out two in particular:
  • If you're interested in material from Effective Modern C++, the most comprehensive seminar I'll be giving on that topic will take place on October 7-8 in London.
  • A special attraction of C++ and Beyond in Stuttgart is looking like it might be a full-blown bar brawl between me and Herb Sutter. In recent weeks, he and I have been going back and forth about the wisdom (or lack thereof) of advising people to use pass-by-value in function interfaces. We've exchanged some posts on this topic in comments on my blog and in posts to a Microsoft C++ MVP mailing list, plus there have been some behind-the-scenes email messages, and at this point, having carefully weighed all the facts, it looks like the only thing we fully agree on is that the other person means well, but is terribly misguided. Herb's German may be better than mine (it definitely is), but when it comes to parameter-passing advice, that boy is going down!
I hope to see you in Bellevue, Cambridge (MA), Bala Cynwyd, Stuttgart, London, Wrocław, Riga, or Berlin later this year.


Wednesday, August 20, 2014

Near-Final Draft of Effective Modern C++ Now Available (plus TOC and sample Item)

Effective Modern C++ is moving closer and closer to reality. This post contains:
  • Information about availability of an almost-final draft of the book.
  • The current (and probably final) table of contents.
  • A link to the I-hope-I-got-it-right-this-time version of my Item on noexcept.

Draft Book Availability

A revised and nearly-final manuscript is now available through O'Reilly's Early Release Program and Safari Books Online's Rough Cuts program. The prose still needs to be sanded down a bit, but practically speaking, this is the final stream of words that will make up the book. Remaining tasks include double-checking the code samples, index generation and final formatting (i.e., typesetting), but this should be quite close to what gets published.

I've left the line numbers in for the online drafts, because that makes it easier for people to report errors to me. The really truly honest-this-is-it version of the manuscript is due to O'Reilly in early September, so if you see anything that needs improvement, please let me know by the end of this month!

Probably-Final Table of Contents

Here's the current table of contents. I'm not wild about the title of the final chapter ("Tweaks"), so if you have suggestions for a better title, let me know.
CHAPTER 1  Deducing Types
  Item 1:  Understand template type deduction. 
  Item 2:  Understand auto type deduction. 
  Item 3:  Understand decltype. 
  Item 4:  Know how to view deduced types. 

CHAPTER 2  auto
  Item 5:  Prefer auto to explicit type declarations. 
  Item 6:  Use the explicitly typed initializer idiom when auto deduces 
           undesired types. 

CHAPTER 3  Moving to Modern C++
  Item 7:  Distinguish between () and {} when creating objects. 
  Item 8:  Prefer nullptr to 0 and NULL. 
  Item 9:  Prefer alias declarations to typedefs. 
  Item 10: Prefer scoped enums to unscoped enums. 
  Item 11: Prefer deleted functions to private undefined ones. 
  Item 12: Declare overriding functions override. 
  Item 13: Prefer const_iterators to iterators. 
  Item 14: Declare functions noexcept if they won't emit exceptions. 
  Item 15: Use constexpr whenever possible. 
  Item 16: Make const member functions thread-safe. 
  Item 17: Understand special member function generation. 

CHAPTER 4  Smart Pointers
  Item 18: Use std::unique_ptr for exclusive-ownership resource management. 
  Item 19: Use std::shared_ptr for shared-ownership resource management. 
  Item 20: Use std::weak_ptr for std::shared_ptr-like pointers that can dangle.
  Item 21: Prefer std::make_unique and std::make_shared to direct use of new.
  Item 22: When using the Pimpl Idiom, define special member functions in the
           implementation file.

CHAPTER 5  Rvalue References, Move Semantics, and Perfect Forwarding
  Item 23: Understand std::move and std::forward. 
  Item 24: Distinguish universal references from rvalue references. 
  Item 25: Use std::move on rvalue references, std::forward on universal
  Item 26: Avoid overloading on universal references. 
  Item 27: Familiarize yourself with alternatives to overloading on universal 
  Item 28: Understand reference collapsing. 
  Item 29: Assume that move operations are not present, not cheap, and not used. 
  Item 30: Familiarize yourself with perfect forwarding failure cases. 

CHAPTER 6  Lambda Expressions
  Item 31: Avoid default capture modes. 
  Item 32: Use init capture to move objects into closures. 
  Item 33: Use decltype on auto&& parameters to std::forward them. 
  Item 34: Prefer lambdas to std::bind. 

CHAPTER 7  The Concurrency API
  Item 35: Prefer task-based programming to thread-based. 
  Item 36: Specify std::launch::async if asynchronicity is essential. 
  Item 37: Make std::threads unjoinable on all paths. 
  Item 38: Be aware of varying thread handle destructor behavior. 
  Item 39: Consider void futures for one-shot event communication. 
  Item 40: Use std::atomic for concurrency, volatile for special memory. 

CHAPTER 8  Tweaks
  Item 41: Consider pass by value for copyable parameters that are cheap to 
           move and always copied.
  Item 42: Consider emplacement instead of insertion. 
Technical writing archeologists may wish to compare this TOC with the versions I showed on 18 March 2014, 5 April 2013, and 29 January 2013. I told you things would change!

Close-to-Final Item on noexcept

I posted drafts of my Item on noexcept on 31 March 2014 and 4 February 2014, so I felt obliged to show you the final-unless-I've-really-made-a-serious-mistake version. Here it is:
Let me know what you think. You've never been shy before, and I have no reason to think things will be different this time around :-)


Wednesday, August 13, 2014

Quick Test Needed for Boost.TypeIndex under Clang

I don't have Clang here (Windows ghetto, sorry), and I haven't been able to find an online Clang compiler that has the Boost headers available, so I'd be grateful if somebody would run the following program under Clang with the latest Boost and let me know (as a blog comment, so that people will know that the work has already been done) what the output is.



#include <iostream>
#include <vector>
#include <boost/type_index.hpp>

template<typename T>
void f(const T& param)
  using std::cout;
  using boost::typeindex::type_id_with_cvr;
  // show T
  cout << "T = "
       << type_id_with_cvr<T>().pretty_name()
       << '\n';
  // show param's type
  cout << "param = "
       << type_id_with_cvr<decltype(param)>().pretty_name()
       << '\n';


class Widget {};

std::vector<Widget> createVec()
  return std::vector<Widget>(5);

int main()
  const auto vw = createVec();
  if (!vw.empty()) {