201 lines
12 KiB
HTML
201 lines
12 KiB
HTML
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
|
|
<title>Boost.StaticString</title>
|
|
<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css">
|
|
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
|
|
<link rel="home" href="index.html" title="Boost.StaticString">
|
|
<link rel="next" href="static_string/ref.html" title="Reference">
|
|
</head>
|
|
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
|
|
<table cellpadding="2" width="100%"><tr>
|
|
<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td>
|
|
<td align="center"><a href="../../../../index.html">Home</a></td>
|
|
<td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td>
|
|
<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
|
|
<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
|
|
<td align="center"><a href="../../../../more/index.htm">More</a></td>
|
|
</tr></table>
|
|
<hr>
|
|
<div class="spirit-nav"><a accesskey="n" href="static_string/ref.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a></div>
|
|
<div class="chapter">
|
|
<div class="titlepage"><div>
|
|
<div><h2 class="title">
|
|
<a name="static_string"></a>Boost.StaticString</h2></div>
|
|
<div><div class="author"><h3 class="author">
|
|
<span class="firstname">Krystian</span> <span class="surname">Stasiowski</span>
|
|
</h3></div></div>
|
|
<div><div class="author"><h3 class="author">
|
|
<span class="firstname">Vinnie</span> <span class="surname">Falco</span>
|
|
</h3></div></div>
|
|
<div><p class="copyright">Copyright © 2019, 2020 Krystian Stasiowski</p></div>
|
|
<div><p class="copyright">Copyright © 2016-2019 Vinnie
|
|
Falco</p></div>
|
|
<div><div class="legalnotice">
|
|
<a name="static_string.legal"></a><p>
|
|
Distributed under the Boost Software License, Version 1.0. (See accompanying
|
|
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
|
|
</p>
|
|
</div></div>
|
|
</div></div>
|
|
<h3>
|
|
<a name="static_string.h0"></a>
|
|
<span class="phrase"><a name="static_string.introduction"></a></span><a class="link" href="index.html#static_string.introduction">Introduction</a>
|
|
</h3>
|
|
<p>
|
|
This library provides a dynamically resizable string of characters with compile-time
|
|
fixed capacity and contiguous embedded storage in which the characters are placed
|
|
within the string object itself. Its API closely resembles that of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>.
|
|
</p>
|
|
<h3>
|
|
<a name="static_string.h1"></a>
|
|
<span class="phrase"><a name="static_string.motivation"></a></span><a class="link" href="index.html#static_string.motivation">Motivation</a>
|
|
</h3>
|
|
<p>
|
|
A fixed capacity string is useful when:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Memory allocation is not possible, e.g., embedded environments without a
|
|
free store, where only a stack and the static memory segment are available.
|
|
</li>
|
|
<li class="listitem">
|
|
Memory allocation imposes an unacceptable performance penalty. e.g., with
|
|
respect to latency.
|
|
</li>
|
|
<li class="listitem">
|
|
Allocation of objects with complex lifetimes in the static-memory segment
|
|
is required.
|
|
</li>
|
|
<li class="listitem">
|
|
A dynamically-resizable string is required within <code class="computeroutput"><span class="keyword">constexpr</span></code>
|
|
functions.
|
|
</li>
|
|
<li class="listitem">
|
|
The storage location of the static_vector elements is required to be within
|
|
the string object itself (e.g. to support <code class="computeroutput"><span class="identifier">memcpy</span></code>
|
|
for serialization purposes).
|
|
</li>
|
|
</ul></div>
|
|
<h3>
|
|
<a name="static_string.h2"></a>
|
|
<span class="phrase"><a name="static_string.requirements"></a></span><a class="link" href="index.html#static_string.requirements">Requirements</a>
|
|
</h3>
|
|
<p>
|
|
The library is usable in two different modes: standalone and Boost dependent.
|
|
This library defaults to Boost dependent mode; standalone mode is opt-in through
|
|
the use of a configuration macro.
|
|
</p>
|
|
<p>
|
|
When in Boost dependent mode, the library requires the use of at least C++11,
|
|
in addition to Boost.Core, Boost.Utility, and Boost.ContainerHash. In standalone
|
|
mode, C++17 is required but no libraries except for the standard library are
|
|
needed.
|
|
</p>
|
|
<h3>
|
|
<a name="static_string.h3"></a>
|
|
<span class="phrase"><a name="static_string.design"></a></span><a class="link" href="index.html#static_string.design">Design</a>
|
|
</h3>
|
|
<p>
|
|
The over-arching design goal is to resemble the interface and behavior of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>
|
|
as much as possible. When any operation would exceed the maximum allowed size
|
|
of the string, <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">length_error</span></code> is thrown if exceptions are enabled.
|
|
All algorithms which throw exceptions provide the strong exception safety guarantee.
|
|
This is intended to be a drop in replacement for <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>.
|
|
</p>
|
|
<p>
|
|
The API of <code class="computeroutput"><span class="identifier">static_string</span></code> only
|
|
diverges from <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code> in few places, one of which is the addition
|
|
of the <code class="computeroutput"><span class="identifier">subview</span></code> function, for
|
|
which this implementation returns a string view instead of <code class="computeroutput"><span class="identifier">static_string</span></code>,
|
|
and certain functions that will never throw are marked as <code class="computeroutput"><span class="keyword">noexcept</span></code>,
|
|
which diverges from those of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>. The
|
|
available overloads for <code class="computeroutput"><span class="identifier">static_string</span></code>
|
|
are identical to those of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>.
|
|
</p>
|
|
<h3>
|
|
<a name="static_string.h4"></a>
|
|
<span class="phrase"><a name="static_string.iterators"></a></span><a class="link" href="index.html#static_string.iterators">Iterators</a>
|
|
</h3>
|
|
<p>
|
|
The iterator invalidation rules differ from those of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
Moving a <code class="computeroutput"><span class="identifier">static_string</span></code> invalidates
|
|
all iterators
|
|
</li>
|
|
<li class="listitem">
|
|
Swapping two <code class="computeroutput"><span class="identifier">static_string</span></code>s
|
|
invalidates all iterators
|
|
</li>
|
|
</ul></div>
|
|
<h3>
|
|
<a name="static_string.h5"></a>
|
|
<span class="phrase"><a name="static_string.optimizations"></a></span><a class="link" href="index.html#static_string.optimizations">Optimizations</a>
|
|
</h3>
|
|
<p>
|
|
Depending on the character type and size used for a specialization of <code class="computeroutput"><span class="identifier">static_string</span></code>, certain optimizations are used
|
|
to reduce the size of the class type. Given the name of a specialization of the
|
|
form <code class="computeroutput"><span class="identifier">basic_static_string</span><span class="special"><</span><span class="identifier">N</span><span class="special">,</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span><span class="special">></span></code>:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
If <code class="computeroutput"><span class="identifier">N</span></code> is 0, then the class
|
|
has no non-static data members. Given two objects <code class="computeroutput"><span class="identifier">a</span></code>
|
|
and <code class="computeroutput"><span class="identifier">b</span></code> of type <code class="computeroutput"><span class="identifier">basic_static_string</span><span class="special"><</span><span class="number">0</span><span class="special">,</span> <span class="identifier">T</span><span class="special">,</span> <span class="identifier">Traits</span><span class="special">></span></code> and <code class="computeroutput"><span class="identifier">static_string</span><span class="special"><</span><span class="number">0</span><span class="special">,</span>
|
|
<span class="identifier">U</span><span class="special">,</span> <span class="identifier">Traits</span><span class="special">></span></code>
|
|
respectively, the pointer value returned by <code class="computeroutput"><span class="identifier">data</span><span class="special">()</span></code> will be the same if <code class="computeroutput"><span class="identifier">T</span></code>
|
|
and <code class="computeroutput"><span class="identifier">U</span></code> are the same.
|
|
</li>
|
|
<li class="listitem">
|
|
Otherwise, the type of the member used to store the size of the <code class="computeroutput"><span class="identifier">static_string</span></code> will be the smallest standard
|
|
unsigned integer type that can represent the value <code class="computeroutput"><span class="identifier">N</span></code>.
|
|
</li>
|
|
</ul></div>
|
|
<h3>
|
|
<a name="static_string.h6"></a>
|
|
<span class="phrase"><a name="static_string.configuration"></a></span><a class="link" href="index.html#static_string.configuration">Configuration</a>
|
|
</h3>
|
|
<p>
|
|
Certain features can be enabled and disabled though defining configuration macros.
|
|
The macros and the associated feature they control are:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">BOOST_STATIC_STRING_STANDALONE</span></code>:
|
|
When defined, the library is put into standalone mode.
|
|
</li></ul></div>
|
|
<h3>
|
|
<a name="static_string.h7"></a>
|
|
<span class="phrase"><a name="static_string.acknowledgments"></a></span><a class="link" href="index.html#static_string.acknowledgments">Acknowledgments</a>
|
|
</h3>
|
|
<p>
|
|
Thanks to <a href="https://github.com/K-ballo" target="_top">Agustín Bergé</a>, <a href="https://github.com/pdimov" target="_top">Peter Dimov</a>, <a href="https://github.com/glenfe" target="_top">Glen
|
|
Fernandes</a>, and <a href="https://github.com/LeonineKing1199" target="_top">Christian
|
|
Mazakas</a> for their constant feedback and guidance during the development
|
|
of this library.
|
|
</p>
|
|
<p>
|
|
The development of this library is sponsored by <a href="https://cppalliance.org" target="_top">The
|
|
C++ Alliance</a>.
|
|
</p>
|
|
<h3>
|
|
<a name="static_string.h8"></a>
|
|
<span class="phrase"><a name="static_string.reference"></a></span><a class="link" href="index.html#static_string.reference">Reference</a>
|
|
</h3>
|
|
<p>
|
|
Defined in namespace <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">static_strings</span></code>:
|
|
</p>
|
|
<p>
|
|
<a class="link" href="static_string/ref/boost__static_strings__basic_static_string.html" title="basic_static_string"><code class="computeroutput"><span class="identifier">basic_static_string</span></code></a>
|
|
</p>
|
|
</div>
|
|
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
|
|
<td align="left"><p><small>Last revised: April 13, 2021 at 16:25:32 GMT</small></p></td>
|
|
<td align="right"><div class="copyright-footer"></div></td>
|
|
</tr></table>
|
|
<hr>
|
|
<div class="spirit-nav"><a accesskey="n" href="static_string/ref.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a></div>
|
|
</body>
|
|
</html>
|