The C++ Standard Library is a collection of essential classes and functions used by millions of C++ programmers on a daily basis. Being part of the ISO Standard of the C++ Programming Language, an implementation is distributed with virtually every C++ compiler. Code written with the C++ Standard Library is therefore portable across compilers and target platforms.

The Library is more than 20 years old. Its initial versions were heavily inspired by a (then proprietary) C++ library called the Standard Template Library (STL) , so much so that many still incorrectly refer to the Standard Library as “the STL.” The STL library pioneered generic programming with templated data structures called containers and algorithms , glued together with the concept of iterators . Most of this work was adapted by the C++ standardization committee, but nevertheless neither library is a true superset of the other.

The C++ Standard Library today is much more than the STL containers and algorithms. For decades, it has featured STL-like string classes, extensive localization facilities, and a stream-based I/O library, as well as all headers of the C Standard Library. In recent years, the C++11 and C++14 editions of the ISO standard have added, among other things, hash map containers, generic smart pointers, a versatile random-number-generation framework, a powerful regular expression library, more expressive utilities for function-style programming, type traits for template metaprogramming, and a portable concurrency library featuring threads, mutexes, condition variables, and atomic variables. Many of these libraries are based on Boost, a collection of open-source C++ libraries.

And this is just the beginning: the C++ community has rarely been as active and alive as in the past few years. The next version of the Standard, tentatively called C++17, is expected to add even more essential classes and functions.

Needless to say, it is hard to know and remember all the possibilities, details, and intricacies of the vast and growing C++ Standard Library. This handy reference guide offers a condensed, well-structured summary of all essential aspects of the C++ Standard Library and is therefore indispensable to any C++ programmer.

You could consult the Standard itself, but it is written in a very detailed, technical style and is primarily targeted at Library implementors. Moreover, it is very long: the C++ Standard Library chapters alone are over 750 pages in length, and those on the C Standard Library encompass another 250 pages. Other reference guides exist but are often outdated, limited (most cover little more than the STL containers and algorithms), or not much shorter than the Standard itself.

This book covers all important aspects of the C++14 and C11 Standard Libraries, some in more detail than others, and always driven by their practical usefulness. You will not find page-long, repetitive examples; obscure, rarely used features; or bloated, lengthy explanations that could be summarized in just a few bullets. Instead, this book strives to be exactly that: a summary. Everything you need to know and watch out for in practice is outlined in a compact, to-the-point style, interspersed with practical tips and short, well-chosen, clarifying examples.

The book is targeted at all C++ programmers, regardless of their proficiency with the language or the Standard Library. If you are new to C++, its tutorial aspects will quickly bring you up to speed with the C++ Standard Library. Even the most experienced C++ programmer, however, will learn a thing or two from the book and find it an indispensable reference and memory aid. The book does not explain the C++ language or syntax itself, but is accessible to anyone with basic C++ knowledge or programming experience.

To compile and execute the code examples given throughout the book, all you need is a sufficiently recent C++ compiler. We leave the choice of compiler entirely up to you, and we further assume you can compile and execute basic C++ programs. All examples contain standard, portable C++ code only and should compile with any C++ compiler that is compliant with the C++14 version of the Standard. We occasionaly indicate known limitations of major compilers, but this is not a real goal of this book. In case of problems, please consult your implementation’s documentation.

Unless otherwise noted, code examples can be copied as is and put inside the main() function of a basic command-line application. Generally, only two headers have to be included to make a code snippet compile: the one being discussed in the context where the example is given, and <iostream> for the command-line output statements (explained shortly). If any other header is required, we try to indicate so in the text. Should we forget, the appendix provides a brief overview of all headers of the Standard Library and their contents. Additionally, you can download compilable source code files for all code snippets from this book from the Apress website ( www.apress.com/9781484218754 ).

Following is the obligatory first example (for once, we show the full program):

Many code samples, including those in earlier chapters, write to the standard output console using std::cout and the << stream operator, even though these facilities of the C++ I/O library are only discussed in detail in Chapter 5 . The stream operator can be used to output virtually all fundamental C++ types, and multiple values can be written on a single line. The I/O manipulator std::endl outputs the newline character ( ) and flushes the output for std::cout to the standard console. Straightforward usage of the std::string class defined in <string> may occur in earlier examples as well. For instance:

More details regarding streams and strings are found in Chapters 5 and 6 , respectively, but this should suffice to get you through the examples in earlier chapters.