C++17 introduced lightweight, non-owning strings referred to as string_view to the standard. Unlike std::string, which performs memory allocations
and copies for most string operations (such as substr), the string_view only observes and does not modify the entry.
This can massively decrease the memory footprint and provide a large optimization for immutable strings for things like parsing and tokenization. As a
result, such a type can be an asset in older c++ versions for systems that may not support the newer standards.
The full type, basic_string_view is templated on a both CharT and Traits to allow viewing of contiguous char-like sequences of data, and for
simple conversion between std::basic_string and basic_string_view.
This string_view implementation is from the BackportCpp library, which aims to
backport library types and utilities from C++14, C++17, and C++20 to be compatible with C++11 compilers. This standalone
library simply offers a subset for those looking for a simple drop-in string_view implementation.
C++17 is still undergoing the standardization process (although currently is considered 'feature-complete'). Although non-owning strings are available in many other libraries, such as boost, Bloomberg STD, QT -- all of them come with rather large dependencies and have slightly different functionality and signatures.
By releasing this library as a standalone include, it provides future-proof support to older compilers with easy accessibility. It also allows using the newer feature-set in older versions, and facilitates easy upgrades to the new standard as compilers upgrade and newer c++ versions become available.
The following compilers are currently being tested through continuous integration with Travis.
Note that bpstd::string_view only works on compiler that provide proper conformance for c++11, meaning this
does not properly work on g++ before 4.8
| Compiler | Operating System |
|---|---|
| g++ 4.9.3 | Ubuntu 14.04.3 TLS |
| g++ 5.3.0 | Ubuntu 14.04.3 TLS |
| g++ 6.1.1 | Ubuntu 14.04.3 TLS |
| clang 3.5.0 | Ubuntu 14.04.3 TLS |
| clang 3.6.2 | Ubuntu 14.04.3 TLS |
| clang 3.8.0 | Ubuntu 14.04.3 TLS |
| clang xcode 6.0 | Darwin Kernel 13.4.0 (OSX 10.9.5) |
| clang xcode 6.1 | Darwin Kernel 14.3.0 (OSX 10.10.3) |
| clang xcode 7.0 | Darwin Kernel 14.5.0 (OSX 10.10.5) |
| clang xcode 7.3 | Darwin Kernel 15.5.0 (OSX 10.11.5) |
| clang xcode 8.0 | Darwin Kernel 15.6.0 (OSX 10.11.6) |
| Visual Studio 14 2015 | Windows Server 2012 R2 (x64) |
The class is licensed under the MIT License:
Copyright © 2016-2021 Matthew Rodusek
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