standard-library

来源： https://stackoverflow.com/questions/16308374/how-do-different-languages-implement-sorting-in-their-standard-libraries

来源： https://stackoverflow.com/questions/51858596/which-standard-library-to-use-in-kotlin

问题 These two traits (std::ops::Add, core::ops::Add) provide the same functionality, and they both use the same example (both utilize std::ops::Add ). Their set of implementors differ somewhat. Should one default to using std::ops::Add ? Why do both, as opposed to one, of them exist? 回答1: There aren't two traits. There is one trait which is exported under several interchangeable names. This is far from unique . Virtually everything in core is also exported from std , and virtually always under

问题 These two traits (std::ops::Add, core::ops::Add) provide the same functionality, and they both use the same example (both utilize std::ops::Add ). Their set of implementors differ somewhat. Should one default to using std::ops::Add ? Why do both, as opposed to one, of them exist? 回答1: There aren't two traits. There is one trait which is exported under several interchangeable names. This is far from unique . Virtually everything in core is also exported from std , and virtually always under

问题 Most of the output methods in Go's io package return (int, error) , for example io.Writer 's Write([]byte) method and the io.WriteString(io.Writer, string) function. However, a few of the output methods, such as io.WriterTo 's WriteTo method, return (int64, error) instead. This makes it inconvenient to implement WriteTo in terms of Write or WriteString without storing an intermediate value and type converting it from int to int64 . What is the reason for this discrepancy? 回答1: It's possible

问题 I am trying to parse a simple CSV file, with data in a format such as: 20.5,20.5,20.5,0.794145,4.05286,0.792519,1 20.5,30.5,20.5,0.753669,3.91888,0.749897,1 20.5,40.5,20.5,0.701055,3.80348,0.695326,1 So, a very simple and fixed format file. I am storing each column of this data into a STL vector. As such I've tried to stay the C++ way using the standard library, and my implementation within a loop looks something like: string field; getline(file,line); stringstream ssline(line); getline(

问题 I am trying to parse a simple CSV file, with data in a format such as: 20.5,20.5,20.5,0.794145,4.05286,0.792519,1 20.5,30.5,20.5,0.753669,3.91888,0.749897,1 20.5,40.5,20.5,0.701055,3.80348,0.695326,1 So, a very simple and fixed format file. I am storing each column of this data into a STL vector. As such I've tried to stay the C++ way using the standard library, and my implementation within a loop looks something like: string field; getline(file,line); stringstream ssline(line); getline(

问题 I am trying to parse a simple CSV file, with data in a format such as: 20.5,20.5,20.5,0.794145,4.05286,0.792519,1 20.5,30.5,20.5,0.753669,3.91888,0.749897,1 20.5,40.5,20.5,0.701055,3.80348,0.695326,1 So, a very simple and fixed format file. I am storing each column of this data into a STL vector. As such I've tried to stay the C++ way using the standard library, and my implementation within a loop looks something like: string field; getline(file,line); stringstream ssline(line); getline(

问题 I'm a bit confused at the moment because I'm planning to include multiple source and header files for the first time in one of my projects. So I'm wondering if this would be the right approach? Do I have to include the string header in every source file that uses it directly? And what about the "stdafx.hpp" header that Visual C++ wants me to include? Would that be the way to go? main.cpp #include "stdafx.hpp" #include <string> //? #include <stringLib1.h> #include <stringLib2.h> using std:

问题 The new operator (or for PODs, malloc/calloc) support a simple and efficient form of failing when allocating large chunks of memory. Say we have this: const size_t sz = GetPotentiallyLargeBufferSize(); // 1M - 1000M T* p = new (nothrow) T[sz]; if(!p) { return sorry_not_enough_mem_would_you_like_to_try_again; } ... Is there any such construct for the std::containers, or will I always have to handle an (expected!!) exception with std::vector and friends? Would there maybe be a way to write a