tr1

问题 What is the current support for tr1 or the new C++0x on the Mac I know that the gcc supplied with XCode is always a couple of versions behind that available from gcc.gnu.org so I was just wondering what the state of play for modern support was. For example do I need to download boost to use shared_ptr or can I get it from std::tr1? 回答1: OS X 10.6 ships with g++ 4.2.1 as well as g++ 4.0, but it should be straightforward to install your own build if you choose to. GNU tools are awesome for that

问题 I'm writing some stuff using the tr1 namespace in VS2008. What will happen when C++xx becomes ratified? Has this happened before with other C++ revisions? Will the tr1 stuff still work or will I have to change all of my include? I realize that I'm making the very large assumption that this ratification will someday occur. I know that most likely none of you work for MS or contribute to GCC, but if you have experience with these kinds of changes, I would appreciate the advice. 回答1: std::tr1

问题 I am just learning about smart pointers, and I am having trouble assigning a pre-existing location of a variable to the standard library's shared pointer. For example, lets say you have an int x, which you do not know the value of. With normal pointers, I just did int* ptr; ptr = &x; I tried both that with shared pointers, and std::tr1::shared_ptr<int> ptr; ptr = std::make_shared<int> (&x) So i'm fairly lost as to how to do it. 回答1: You wouldn't (usually) make a smart pointer point to an

问题 We are programming a logging library that keeps itself in a .hpp file. We would like to include <tr1/unordered_map> (if the compiler supports TR1,) or the standard <map> otherwise. Is there a standard way of checking at compile time if tr1 is available or not? I was thinking that the same way that the " __cplusplus " define symbol is present, there could have been defined a " __cxx__tr1 " or something like that. I haven't seen that in the drafts for TR1, so I assume it is not present, but I

问题 The boost::function FAQ item 3 specifically addresses the scenario I am interested in: Why are there workarounds for void returns? C++ allows them! Void returns are permitted by the C++ standard, as in this code snippet: void f(); void g() { return f(); } This is a valid usage of boost::function because void returns are not used. With void returns, we would attempting to compile ill-formed code similar to: int f(); void g() { return f(); } In essence, not using void returns allows boost:

问题 I am working on a platform with a gcc compiler however boost cannot compile on it. I am wondering what is the proper way to include the shared_ptr in std:tr1 on gcc? the file i looked in said not to include it directly, from what i can tell no other file includes it either :| 回答1: In G++ 4.3 , #include <tr1/memory> should do the trick. You'll find shared_ptr at std::tr1::shared_ptr . 回答2: Boost itself has the answer. 回答3: Boost can not compile on it? Most of the boost library doesn't need to

问题 I am working on a platform with a gcc compiler however boost cannot compile on it. I am wondering what is the proper way to include the shared_ptr in std:tr1 on gcc? the file i looked in said not to include it directly, from what i can tell no other file includes it either :| 回答1: In G++ 4.3 , #include <tr1/memory> should do the trick. You'll find shared_ptr at std::tr1::shared_ptr . 回答2: Boost itself has the answer. 回答3: Boost can not compile on it? Most of the boost library doesn't need to

问题 In Perl, I can do this: $text = '1747239'; @matches = ($text =~ m/(\d)/g); # @matches now contains ('1', '7', '4', '7', '2', '3', '9') Using C++ regex matching, what's the best way to replicate this behaviour so that I get a match set including all the matches? I have this at the moment:- compiledRegex = std::regex(regex, std::tr1::regex_constants::extended); regex_search(text, results, compiledRegex); int count = results.size(); // Alloc pointer array based on count * sizeof(mystruct). for (

问题 I have a project which I would like to make more use of smart pointers. Overall, I have been successful in this goal. However, I've come across one things which I'm not sure what the "best practice" is. Basically I would like to return a "pointer" from a function, but require that the user hold it in a smart pointer. Not only that, I don't want to mandate a particular smart pointer (shared vs. scoped). The problem is mostly that there doesn't seem be to a proper way to upgrade a scoped_ptr to

问题 #include <string> #include <tr1/regex> #include "TextProcessing.h" const std::string URL_PATTERN("((http://)[-a-zA-Z0-9@:%_\\+.~#?&//=]+)"); const std::string REPLACEMENT("<a href=\"$&\"\">$&</a>"); std::string textprocessing::processLinks(const std::string & text) { // essentially the same regex as in the previous example, but using a dynamic regex std::tr1::regex url(URL_PATTERN); // As in Perl, $& is a reference to the sub-string that matched the regex return std::tr1::regex_replace(text,