// Components for manipulating sequences of characters -*- C++ -*-
// Copyright (C) 1997-2021 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// .
/** @file bits/basic_string.tcc
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{string}
*/
//
// ISO C++ 14882: 21 Strings library
//
// Written by Jason Merrill based upon the specification by Takanori Adachi
// in ANSI X3J16/94-0013R2. Rewritten by Nathan Myers to ISO-14882.
// Non-reference-counted implementation written by Paolo Carlini and
// updated by Jonathan Wakely for ISO-14882-2011.
#ifndef _BASIC_STRING_TCC
#define _BASIC_STRING_TCC 1
#pragma GCC system_header
#include
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
#if _GLIBCXX_USE_CXX11_ABI
template
const typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::npos;
template
void
basic_string<_CharT, _Traits, _Alloc>::
swap(basic_string& __s) _GLIBCXX_NOEXCEPT
{
if (this == &__s)
return;
_Alloc_traits::_S_on_swap(_M_get_allocator(), __s._M_get_allocator());
if (_M_is_local())
if (__s._M_is_local())
{
if (length() && __s.length())
{
_CharT __tmp_data[_S_local_capacity + 1];
traits_type::copy(__tmp_data, __s._M_local_buf,
_S_local_capacity + 1);
traits_type::copy(__s._M_local_buf, _M_local_buf,
_S_local_capacity + 1);
traits_type::copy(_M_local_buf, __tmp_data,
_S_local_capacity + 1);
}
else if (__s.length())
{
traits_type::copy(_M_local_buf, __s._M_local_buf,
_S_local_capacity + 1);
_M_length(__s.length());
__s._M_set_length(0);
return;
}
else if (length())
{
traits_type::copy(__s._M_local_buf, _M_local_buf,
_S_local_capacity + 1);
__s._M_length(length());
_M_set_length(0);
return;
}
}
else
{
const size_type __tmp_capacity = __s._M_allocated_capacity;
traits_type::copy(__s._M_local_buf, _M_local_buf,
_S_local_capacity + 1);
_M_data(__s._M_data());
__s._M_data(__s._M_local_buf);
_M_capacity(__tmp_capacity);
}
else
{
const size_type __tmp_capacity = _M_allocated_capacity;
if (__s._M_is_local())
{
traits_type::copy(_M_local_buf, __s._M_local_buf,
_S_local_capacity + 1);
__s._M_data(_M_data());
_M_data(_M_local_buf);
}
else
{
pointer __tmp_ptr = _M_data();
_M_data(__s._M_data());
__s._M_data(__tmp_ptr);
_M_capacity(__s._M_allocated_capacity);
}
__s._M_capacity(__tmp_capacity);
}
const size_type __tmp_length = length();
_M_length(__s.length());
__s._M_length(__tmp_length);
}
template
typename basic_string<_CharT, _Traits, _Alloc>::pointer
basic_string<_CharT, _Traits, _Alloc>::
_M_create(size_type& __capacity, size_type __old_capacity)
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 83. String::npos vs. string::max_size()
if (__capacity > max_size())
std::__throw_length_error(__N("basic_string::_M_create"));
// The below implements an exponential growth policy, necessary to
// meet amortized linear time requirements of the library: see
// http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
{
__capacity = 2 * __old_capacity;
// Never allocate a string bigger than max_size.
if (__capacity > max_size())
__capacity = max_size();
}
// NB: Need an array of char_type[__capacity], plus a terminating
// null char_type() element.
return _Alloc_traits::allocate(_M_get_allocator(), __capacity + 1);
}
// NB: This is the special case for Input Iterators, used in
// istreambuf_iterators, etc.
// Input Iterators have a cost structure very different from
// pointers, calling for a different coding style.
template
template
void
basic_string<_CharT, _Traits, _Alloc>::
_M_construct(_InIterator __beg, _InIterator __end,
std::input_iterator_tag)
{
size_type __len = 0;
size_type __capacity = size_type(_S_local_capacity);
while (__beg != __end && __len < __capacity)
{
_M_data()[__len++] = *__beg;
++__beg;
}
__try
{
while (__beg != __end)
{
if (__len == __capacity)
{
// Allocate more space.
__capacity = __len + 1;
pointer __another = _M_create(__capacity, __len);
this->_S_copy(__another, _M_data(), __len);
_M_dispose();
_M_data(__another);
_M_capacity(__capacity);
}
_M_data()[__len++] = *__beg;
++__beg;
}
}
__catch(...)
{
_M_dispose();
__throw_exception_again;
}
_M_set_length(__len);
}
template
template
void
basic_string<_CharT, _Traits, _Alloc>::
_M_construct(_InIterator __beg, _InIterator __end,
std::forward_iterator_tag)
{
// NB: Not required, but considered best practice.
if (__gnu_cxx::__is_null_pointer(__beg) && __beg != __end)
std::__throw_logic_error(__N("basic_string::"
"_M_construct null not valid"));
size_type __dnew = static_cast(std::distance(__beg, __end));
if (__dnew > size_type(_S_local_capacity))
{
_M_data(_M_create(__dnew, size_type(0)));
_M_capacity(__dnew);
}
// Check for out_of_range and length_error exceptions.
__try
{ this->_S_copy_chars(_M_data(), __beg, __end); }
__catch(...)
{
_M_dispose();
__throw_exception_again;
}
_M_set_length(__dnew);
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
_M_construct(size_type __n, _CharT __c)
{
if (__n > size_type(_S_local_capacity))
{
_M_data(_M_create(__n, size_type(0)));
_M_capacity(__n);
}
if (__n)
this->_S_assign(_M_data(), __n, __c);
_M_set_length(__n);
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
_M_assign(const basic_string& __str)
{
if (this != &__str)
{
const size_type __rsize = __str.length();
const size_type __capacity = capacity();
if (__rsize > __capacity)
{
size_type __new_capacity = __rsize;
pointer __tmp = _M_create(__new_capacity, __capacity);
_M_dispose();
_M_data(__tmp);
_M_capacity(__new_capacity);
}
if (__rsize)
this->_S_copy(_M_data(), __str._M_data(), __rsize);
_M_set_length(__rsize);
}
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
reserve(size_type __res)
{
const size_type __capacity = capacity();
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2968. Inconsistencies between basic_string reserve and
// vector/unordered_map/unordered_set reserve functions
// P0966 reserve should not shrink
if (__res <= __capacity)
return;
pointer __tmp = _M_create(__res, __capacity);
this->_S_copy(__tmp, _M_data(), length() + 1);
_M_dispose();
_M_data(__tmp);
_M_capacity(__res);
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
_M_mutate(size_type __pos, size_type __len1, const _CharT* __s,
size_type __len2)
{
const size_type __how_much = length() - __pos - __len1;
size_type __new_capacity = length() + __len2 - __len1;
pointer __r = _M_create(__new_capacity, capacity());
if (__pos)
this->_S_copy(__r, _M_data(), __pos);
if (__s && __len2)
this->_S_copy(__r + __pos, __s, __len2);
if (__how_much)
this->_S_copy(__r + __pos + __len2,
_M_data() + __pos + __len1, __how_much);
_M_dispose();
_M_data(__r);
_M_capacity(__new_capacity);
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
_M_erase(size_type __pos, size_type __n)
{
const size_type __how_much = length() - __pos - __n;
if (__how_much && __n)
this->_S_move(_M_data() + __pos, _M_data() + __pos + __n, __how_much);
_M_set_length(length() - __n);
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
reserve()
{
if (_M_is_local())
return;
const size_type __length = length();
const size_type __capacity = _M_allocated_capacity;
if (__length <= size_type(_S_local_capacity))
{
this->_S_copy(_M_local_data(), _M_data(), __length + 1);
_M_destroy(__capacity);
_M_data(_M_local_data());
}
#if __cpp_exceptions
else if (__length < __capacity)
try
{
pointer __tmp
= _Alloc_traits::allocate(_M_get_allocator(), __length + 1);
this->_S_copy(__tmp, _M_data(), __length + 1);
_M_dispose();
_M_data(__tmp);
_M_capacity(__length);
}
catch (const __cxxabiv1::__forced_unwind&)
{ throw; }
catch (...)
{ /* swallow the exception */ }
#endif
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
resize(size_type __n, _CharT __c)
{
const size_type __size = this->size();
if (__size < __n)
this->append(__n - __size, __c);
else if (__n < __size)
this->_M_set_length(__n);
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
_M_append(const _CharT* __s, size_type __n)
{
const size_type __len = __n + this->size();
if (__len <= this->capacity())
{
if (__n)
this->_S_copy(this->_M_data() + this->size(), __s, __n);
}
else
this->_M_mutate(this->size(), size_type(0), __s, __n);
this->_M_set_length(__len);
return *this;
}
template
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
_M_replace_dispatch(const_iterator __i1, const_iterator __i2,
_InputIterator __k1, _InputIterator __k2,
std::__false_type)
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2788. unintentionally require a default constructible allocator
const basic_string __s(__k1, __k2, this->get_allocator());
const size_type __n1 = __i2 - __i1;
return _M_replace(__i1 - begin(), __n1, __s._M_data(),
__s.size());
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
_M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
_CharT __c)
{
_M_check_length(__n1, __n2, "basic_string::_M_replace_aux");
const size_type __old_size = this->size();
const size_type __new_size = __old_size + __n2 - __n1;
if (__new_size <= this->capacity())
{
pointer __p = this->_M_data() + __pos1;
const size_type __how_much = __old_size - __pos1 - __n1;
if (__how_much && __n1 != __n2)
this->_S_move(__p + __n2, __p + __n1, __how_much);
}
else
this->_M_mutate(__pos1, __n1, 0, __n2);
if (__n2)
this->_S_assign(this->_M_data() + __pos1, __n2, __c);
this->_M_set_length(__new_size);
return *this;
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
_M_replace(size_type __pos, size_type __len1, const _CharT* __s,
const size_type __len2)
{
_M_check_length(__len1, __len2, "basic_string::_M_replace");
const size_type __old_size = this->size();
const size_type __new_size = __old_size + __len2 - __len1;
if (__new_size <= this->capacity())
{
pointer __p = this->_M_data() + __pos;
const size_type __how_much = __old_size - __pos - __len1;
if (_M_disjunct(__s))
{
if (__how_much && __len1 != __len2)
this->_S_move(__p + __len2, __p + __len1, __how_much);
if (__len2)
this->_S_copy(__p, __s, __len2);
}
else
{
// Work in-place.
if (__len2 && __len2 <= __len1)
this->_S_move(__p, __s, __len2);
if (__how_much && __len1 != __len2)
this->_S_move(__p + __len2, __p + __len1, __how_much);
if (__len2 > __len1)
{
if (__s + __len2 <= __p + __len1)
this->_S_move(__p, __s, __len2);
else if (__s >= __p + __len1)
this->_S_copy(__p, __s + __len2 - __len1, __len2);
else
{
const size_type __nleft = (__p + __len1) - __s;
this->_S_move(__p, __s, __nleft);
this->_S_copy(__p + __nleft, __p + __len2,
__len2 - __nleft);
}
}
}
}
else
this->_M_mutate(__pos, __len1, __s, __len2);
this->_M_set_length(__new_size);
return *this;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
copy(_CharT* __s, size_type __n, size_type __pos) const
{
_M_check(__pos, "basic_string::copy");
__n = _M_limit(__pos, __n);
__glibcxx_requires_string_len(__s, __n);
if (__n)
_S_copy(__s, _M_data() + __pos, __n);
// 21.3.5.7 par 3: do not append null. (good.)
return __n;
}
#else // !_GLIBCXX_USE_CXX11_ABI
template
const typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
_Rep::_S_max_size = (((npos - sizeof(_Rep_base))/sizeof(_CharT)) - 1) / 4;
template
const _CharT
basic_string<_CharT, _Traits, _Alloc>::
_Rep::_S_terminal = _CharT();
template
const typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::npos;
// Linker sets _S_empty_rep_storage to all 0s (one reference, empty string)
// at static init time (before static ctors are run).
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::_Rep::_S_empty_rep_storage[
(sizeof(_Rep_base) + sizeof(_CharT) + sizeof(size_type) - 1) /
sizeof(size_type)];
// NB: This is the special case for Input Iterators, used in
// istreambuf_iterators, etc.
// Input Iterators have a cost structure very different from
// pointers, calling for a different coding style.
template
template
_CharT*
basic_string<_CharT, _Traits, _Alloc>::
_S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
input_iterator_tag)
{
#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
if (__beg == __end && __a == _Alloc())
return _S_empty_rep()._M_refdata();
#endif
// Avoid reallocation for common case.
_CharT __buf[128];
size_type __len = 0;
while (__beg != __end && __len < sizeof(__buf) / sizeof(_CharT))
{
__buf[__len++] = *__beg;
++__beg;
}
_Rep* __r = _Rep::_S_create(__len, size_type(0), __a);
_M_copy(__r->_M_refdata(), __buf, __len);
__try
{
while (__beg != __end)
{
if (__len == __r->_M_capacity)
{
// Allocate more space.
_Rep* __another = _Rep::_S_create(__len + 1, __len, __a);
_M_copy(__another->_M_refdata(), __r->_M_refdata(), __len);
__r->_M_destroy(__a);
__r = __another;
}
__r->_M_refdata()[__len++] = *__beg;
++__beg;
}
}
__catch(...)
{
__r->_M_destroy(__a);
__throw_exception_again;
}
__r->_M_set_length_and_sharable(__len);
return __r->_M_refdata();
}
template
template
_CharT*
basic_string<_CharT, _Traits, _Alloc>::
_S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
forward_iterator_tag)
{
#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
if (__beg == __end && __a == _Alloc())
return _S_empty_rep()._M_refdata();
#endif
// NB: Not required, but considered best practice.
if (__gnu_cxx::__is_null_pointer(__beg) && __beg != __end)
__throw_logic_error(__N("basic_string::_S_construct null not valid"));
const size_type __dnew = static_cast(std::distance(__beg,
__end));
// Check for out_of_range and length_error exceptions.
_Rep* __r = _Rep::_S_create(__dnew, size_type(0), __a);
__try
{ _S_copy_chars(__r->_M_refdata(), __beg, __end); }
__catch(...)
{
__r->_M_destroy(__a);
__throw_exception_again;
}
__r->_M_set_length_and_sharable(__dnew);
return __r->_M_refdata();
}
template
_CharT*
basic_string<_CharT, _Traits, _Alloc>::
_S_construct(size_type __n, _CharT __c, const _Alloc& __a)
{
#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
if (__n == 0 && __a == _Alloc())
return _S_empty_rep()._M_refdata();
#endif
// Check for out_of_range and length_error exceptions.
_Rep* __r = _Rep::_S_create(__n, size_type(0), __a);
if (__n)
_M_assign(__r->_M_refdata(), __n, __c);
__r->_M_set_length_and_sharable(__n);
return __r->_M_refdata();
}
template
basic_string<_CharT, _Traits, _Alloc>::
basic_string(const basic_string& __str, size_type __pos, const _Alloc& __a)
: _M_dataplus(_S_construct(__str._M_data()
+ __str._M_check(__pos,
"basic_string::basic_string"),
__str._M_data() + __str._M_limit(__pos, npos)
+ __pos, __a), __a)
{ }
template
basic_string<_CharT, _Traits, _Alloc>::
basic_string(const basic_string& __str, size_type __pos, size_type __n)
: _M_dataplus(_S_construct(__str._M_data()
+ __str._M_check(__pos,
"basic_string::basic_string"),
__str._M_data() + __str._M_limit(__pos, __n)
+ __pos, _Alloc()), _Alloc())
{ }
template
basic_string<_CharT, _Traits, _Alloc>::
basic_string(const basic_string& __str, size_type __pos,
size_type __n, const _Alloc& __a)
: _M_dataplus(_S_construct(__str._M_data()
+ __str._M_check(__pos,
"basic_string::basic_string"),
__str._M_data() + __str._M_limit(__pos, __n)
+ __pos, __a), __a)
{ }
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
assign(const basic_string& __str)
{
if (_M_rep() != __str._M_rep())
{
// XXX MT
const allocator_type __a = this->get_allocator();
_CharT* __tmp = __str._M_rep()->_M_grab(__a, __str.get_allocator());
_M_rep()->_M_dispose(__a);
_M_data(__tmp);
}
return *this;
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
assign(const _CharT* __s, size_type __n)
{
__glibcxx_requires_string_len(__s, __n);
_M_check_length(this->size(), __n, "basic_string::assign");
if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
return _M_replace_safe(size_type(0), this->size(), __s, __n);
else
{
// Work in-place.
const size_type __pos = __s - _M_data();
if (__pos >= __n)
_M_copy(_M_data(), __s, __n);
else if (__pos)
_M_move(_M_data(), __s, __n);
_M_rep()->_M_set_length_and_sharable(__n);
return *this;
}
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
append(size_type __n, _CharT __c)
{
if (__n)
{
_M_check_length(size_type(0), __n, "basic_string::append");
const size_type __len = __n + this->size();
if (__len > this->capacity() || _M_rep()->_M_is_shared())
this->reserve(__len);
_M_assign(_M_data() + this->size(), __n, __c);
_M_rep()->_M_set_length_and_sharable(__len);
}
return *this;
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
append(const _CharT* __s, size_type __n)
{
__glibcxx_requires_string_len(__s, __n);
if (__n)
{
_M_check_length(size_type(0), __n, "basic_string::append");
const size_type __len = __n + this->size();
if (__len > this->capacity() || _M_rep()->_M_is_shared())
{
if (_M_disjunct(__s))
this->reserve(__len);
else
{
const size_type __off = __s - _M_data();
this->reserve(__len);
__s = _M_data() + __off;
}
}
_M_copy(_M_data() + this->size(), __s, __n);
_M_rep()->_M_set_length_and_sharable(__len);
}
return *this;
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
append(const basic_string& __str)
{
const size_type __size = __str.size();
if (__size)
{
const size_type __len = __size + this->size();
if (__len > this->capacity() || _M_rep()->_M_is_shared())
this->reserve(__len);
_M_copy(_M_data() + this->size(), __str._M_data(), __size);
_M_rep()->_M_set_length_and_sharable(__len);
}
return *this;
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
append(const basic_string& __str, size_type __pos, size_type __n)
{
__str._M_check(__pos, "basic_string::append");
__n = __str._M_limit(__pos, __n);
if (__n)
{
const size_type __len = __n + this->size();
if (__len > this->capacity() || _M_rep()->_M_is_shared())
this->reserve(__len);
_M_copy(_M_data() + this->size(), __str._M_data() + __pos, __n);
_M_rep()->_M_set_length_and_sharable(__len);
}
return *this;
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
insert(size_type __pos, const _CharT* __s, size_type __n)
{
__glibcxx_requires_string_len(__s, __n);
_M_check(__pos, "basic_string::insert");
_M_check_length(size_type(0), __n, "basic_string::insert");
if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
return _M_replace_safe(__pos, size_type(0), __s, __n);
else
{
// Work in-place.
const size_type __off = __s - _M_data();
_M_mutate(__pos, 0, __n);
__s = _M_data() + __off;
_CharT* __p = _M_data() + __pos;
if (__s + __n <= __p)
_M_copy(__p, __s, __n);
else if (__s >= __p)
_M_copy(__p, __s + __n, __n);
else
{
const size_type __nleft = __p - __s;
_M_copy(__p, __s, __nleft);
_M_copy(__p + __nleft, __p + __n, __n - __nleft);
}
return *this;
}
}
template
typename basic_string<_CharT, _Traits, _Alloc>::iterator
basic_string<_CharT, _Traits, _Alloc>::
erase(iterator __first, iterator __last)
{
_GLIBCXX_DEBUG_PEDASSERT(__first >= _M_ibegin() && __first <= __last
&& __last <= _M_iend());
// NB: This isn't just an optimization (bail out early when
// there is nothing to do, really), it's also a correctness
// issue vs MT, see libstdc++/40518.
const size_type __size = __last - __first;
if (__size)
{
const size_type __pos = __first - _M_ibegin();
_M_mutate(__pos, __size, size_type(0));
_M_rep()->_M_set_leaked();
return iterator(_M_data() + __pos);
}
else
return __first;
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
replace(size_type __pos, size_type __n1, const _CharT* __s,
size_type __n2)
{
__glibcxx_requires_string_len(__s, __n2);
_M_check(__pos, "basic_string::replace");
__n1 = _M_limit(__pos, __n1);
_M_check_length(__n1, __n2, "basic_string::replace");
bool __left;
if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
return _M_replace_safe(__pos, __n1, __s, __n2);
else if ((__left = __s + __n2 <= _M_data() + __pos)
|| _M_data() + __pos + __n1 <= __s)
{
// Work in-place: non-overlapping case.
size_type __off = __s - _M_data();
__left ? __off : (__off += __n2 - __n1);
_M_mutate(__pos, __n1, __n2);
_M_copy(_M_data() + __pos, _M_data() + __off, __n2);
return *this;
}
else
{
// Todo: overlapping case.
const basic_string __tmp(__s, __n2);
return _M_replace_safe(__pos, __n1, __tmp._M_data(), __n2);
}
}
template
void
basic_string<_CharT, _Traits, _Alloc>::_Rep::
_M_destroy(const _Alloc& __a) throw ()
{
const size_type __size = sizeof(_Rep_base) +
(this->_M_capacity + 1) * sizeof(_CharT);
_Raw_bytes_alloc(__a).deallocate(reinterpret_cast(this), __size);
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
_M_leak_hard()
{
#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
if (_M_rep() == &_S_empty_rep())
return;
#endif
if (_M_rep()->_M_is_shared())
_M_mutate(0, 0, 0);
_M_rep()->_M_set_leaked();
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
_M_mutate(size_type __pos, size_type __len1, size_type __len2)
{
const size_type __old_size = this->size();
const size_type __new_size = __old_size + __len2 - __len1;
const size_type __how_much = __old_size - __pos - __len1;
if (__new_size > this->capacity() || _M_rep()->_M_is_shared())
{
// Must reallocate.
const allocator_type __a = get_allocator();
_Rep* __r = _Rep::_S_create(__new_size, this->capacity(), __a);
if (__pos)
_M_copy(__r->_M_refdata(), _M_data(), __pos);
if (__how_much)
_M_copy(__r->_M_refdata() + __pos + __len2,
_M_data() + __pos + __len1, __how_much);
_M_rep()->_M_dispose(__a);
_M_data(__r->_M_refdata());
}
else if (__how_much && __len1 != __len2)
{
// Work in-place.
_M_move(_M_data() + __pos + __len2,
_M_data() + __pos + __len1, __how_much);
}
_M_rep()->_M_set_length_and_sharable(__new_size);
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
reserve(size_type __res)
{
const size_type __capacity = capacity();
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2968. Inconsistencies between basic_string reserve and
// vector/unordered_map/unordered_set reserve functions
// P0966 reserve should not shrink
if (__res <= __capacity)
{
if (!_M_rep()->_M_is_shared())
return;
// unshare, but keep same capacity
__res = __capacity;
}
const allocator_type __a = get_allocator();
_CharT* __tmp = _M_rep()->_M_clone(__a, __res - this->size());
_M_rep()->_M_dispose(__a);
_M_data(__tmp);
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
swap(basic_string& __s)
_GLIBCXX_NOEXCEPT_IF(allocator_traits<_Alloc>::is_always_equal::value)
{
if (_M_rep()->_M_is_leaked())
_M_rep()->_M_set_sharable();
if (__s._M_rep()->_M_is_leaked())
__s._M_rep()->_M_set_sharable();
if (this->get_allocator() == __s.get_allocator())
{
_CharT* __tmp = _M_data();
_M_data(__s._M_data());
__s._M_data(__tmp);
}
// The code below can usually be optimized away.
else
{
const basic_string __tmp1(_M_ibegin(), _M_iend(),
__s.get_allocator());
const basic_string __tmp2(__s._M_ibegin(), __s._M_iend(),
this->get_allocator());
*this = __tmp2;
__s = __tmp1;
}
}
template
typename basic_string<_CharT, _Traits, _Alloc>::_Rep*
basic_string<_CharT, _Traits, _Alloc>::_Rep::
_S_create(size_type __capacity, size_type __old_capacity,
const _Alloc& __alloc)
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 83. String::npos vs. string::max_size()
if (__capacity > _S_max_size)
__throw_length_error(__N("basic_string::_S_create"));
// The standard places no restriction on allocating more memory
// than is strictly needed within this layer at the moment or as
// requested by an explicit application call to reserve(n).
// Many malloc implementations perform quite poorly when an
// application attempts to allocate memory in a stepwise fashion
// growing each allocation size by only 1 char. Additionally,
// it makes little sense to allocate less linear memory than the
// natural blocking size of the malloc implementation.
// Unfortunately, we would need a somewhat low-level calculation
// with tuned parameters to get this perfect for any particular
// malloc implementation. Fortunately, generalizations about
// common features seen among implementations seems to suffice.
// __pagesize need not match the actual VM page size for good
// results in practice, thus we pick a common value on the low
// side. __malloc_header_size is an estimate of the amount of
// overhead per memory allocation (in practice seen N * sizeof
// (void*) where N is 0, 2 or 4). According to folklore,
// picking this value on the high side is better than
// low-balling it (especially when this algorithm is used with
// malloc implementations that allocate memory blocks rounded up
// to a size which is a power of 2).
const size_type __pagesize = 4096;
const size_type __malloc_header_size = 4 * sizeof(void*);
// The below implements an exponential growth policy, necessary to
// meet amortized linear time requirements of the library: see
// http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
// It's active for allocations requiring an amount of memory above
// system pagesize. This is consistent with the requirements of the
// standard: http://gcc.gnu.org/ml/libstdc++/2001-07/msg00130.html
if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
__capacity = 2 * __old_capacity;
// NB: Need an array of char_type[__capacity], plus a terminating
// null char_type() element, plus enough for the _Rep data structure.
// Whew. Seemingly so needy, yet so elemental.
size_type __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
const size_type __adj_size = __size + __malloc_header_size;
if (__adj_size > __pagesize && __capacity > __old_capacity)
{
const size_type __extra = __pagesize - __adj_size % __pagesize;
__capacity += __extra / sizeof(_CharT);
// Never allocate a string bigger than _S_max_size.
if (__capacity > _S_max_size)
__capacity = _S_max_size;
__size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
}
// NB: Might throw, but no worries about a leak, mate: _Rep()
// does not throw.
void* __place = _Raw_bytes_alloc(__alloc).allocate(__size);
_Rep *__p = new (__place) _Rep;
__p->_M_capacity = __capacity;
// ABI compatibility - 3.4.x set in _S_create both
// _M_refcount and _M_length. All callers of _S_create
// in basic_string.tcc then set just _M_length.
// In 4.0.x and later both _M_refcount and _M_length
// are initialized in the callers, unfortunately we can
// have 3.4.x compiled code with _S_create callers inlined
// calling 4.0.x+ _S_create.
__p->_M_set_sharable();
return __p;
}
template
_CharT*
basic_string<_CharT, _Traits, _Alloc>::_Rep::
_M_clone(const _Alloc& __alloc, size_type __res)
{
// Requested capacity of the clone.
const size_type __requested_cap = this->_M_length + __res;
_Rep* __r = _Rep::_S_create(__requested_cap, this->_M_capacity,
__alloc);
if (this->_M_length)
_M_copy(__r->_M_refdata(), _M_refdata(), this->_M_length);
__r->_M_set_length_and_sharable(this->_M_length);
return __r->_M_refdata();
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
resize(size_type __n, _CharT __c)
{
const size_type __size = this->size();
_M_check_length(__size, __n, "basic_string::resize");
if (__size < __n)
this->append(__n - __size, __c);
else if (__n < __size)
this->erase(__n);
// else nothing (in particular, avoid calling _M_mutate() unnecessarily.)
}
template
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
_M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
_InputIterator __k2, __false_type)
{
const basic_string __s(__k1, __k2);
const size_type __n1 = __i2 - __i1;
_M_check_length(__n1, __s.size(), "basic_string::_M_replace_dispatch");
return _M_replace_safe(__i1 - _M_ibegin(), __n1, __s._M_data(),
__s.size());
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
_M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
_CharT __c)
{
_M_check_length(__n1, __n2, "basic_string::_M_replace_aux");
_M_mutate(__pos1, __n1, __n2);
if (__n2)
_M_assign(_M_data() + __pos1, __n2, __c);
return *this;
}
template
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
_M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
size_type __n2)
{
_M_mutate(__pos1, __n1, __n2);
if (__n2)
_M_copy(_M_data() + __pos1, __s, __n2);
return *this;
}
template
void
basic_string<_CharT, _Traits, _Alloc>::
reserve()
{
#if __cpp_exceptions
if (length() < capacity() || _M_rep()->_M_is_shared())
try
{
const allocator_type __a = get_allocator();
_CharT* __tmp = _M_rep()->_M_clone(__a);
_M_rep()->_M_dispose(__a);
_M_data(__tmp);
}
catch (const __cxxabiv1::__forced_unwind&)
{ throw; }
catch (...)
{ /* swallow the exception */ }
#endif
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
copy(_CharT* __s, size_type __n, size_type __pos) const
{
_M_check(__pos, "basic_string::copy");
__n = _M_limit(__pos, __n);
__glibcxx_requires_string_len(__s, __n);
if (__n)
_M_copy(__s, _M_data() + __pos, __n);
// 21.3.5.7 par 3: do not append null. (good.)
return __n;
}
#endif // !_GLIBCXX_USE_CXX11_ABI
template
basic_string<_CharT, _Traits, _Alloc>
operator+(const _CharT* __lhs,
const basic_string<_CharT, _Traits, _Alloc>& __rhs)
{
__glibcxx_requires_string(__lhs);
typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
typedef typename __string_type::size_type __size_type;
typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
rebind<_CharT>::other _Char_alloc_type;
typedef __gnu_cxx::__alloc_traits<_Char_alloc_type> _Alloc_traits;
const __size_type __len = _Traits::length(__lhs);
__string_type __str(_Alloc_traits::_S_select_on_copy(
__rhs.get_allocator()));
__str.reserve(__len + __rhs.size());
__str.append(__lhs, __len);
__str.append(__rhs);
return __str;
}
template
basic_string<_CharT, _Traits, _Alloc>
operator+(_CharT __lhs, const basic_string<_CharT, _Traits, _Alloc>& __rhs)
{
typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
typedef typename __string_type::size_type __size_type;
typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
rebind<_CharT>::other _Char_alloc_type;
typedef __gnu_cxx::__alloc_traits<_Char_alloc_type> _Alloc_traits;
__string_type __str(_Alloc_traits::_S_select_on_copy(
__rhs.get_allocator()));
const __size_type __len = __rhs.size();
__str.reserve(__len + 1);
__str.append(__size_type(1), __lhs);
__str.append(__rhs);
return __str;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
find(const _CharT* __s, size_type __pos, size_type __n) const
_GLIBCXX_NOEXCEPT
{
__glibcxx_requires_string_len(__s, __n);
const size_type __size = this->size();
if (__n == 0)
return __pos <= __size ? __pos : npos;
if (__pos >= __size)
return npos;
const _CharT __elem0 = __s[0];
const _CharT* const __data = data();
const _CharT* __first = __data + __pos;
const _CharT* const __last = __data + __size;
size_type __len = __size - __pos;
while (__len >= __n)
{
// Find the first occurrence of __elem0:
__first = traits_type::find(__first, __len - __n + 1, __elem0);
if (!__first)
return npos;
// Compare the full strings from the first occurrence of __elem0.
// We already know that __first[0] == __s[0] but compare them again
// anyway because __s is probably aligned, which helps memcmp.
if (traits_type::compare(__first, __s, __n) == 0)
return __first - __data;
__len = __last - ++__first;
}
return npos;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
find(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
{
size_type __ret = npos;
const size_type __size = this->size();
if (__pos < __size)
{
const _CharT* __data = _M_data();
const size_type __n = __size - __pos;
const _CharT* __p = traits_type::find(__data + __pos, __n, __c);
if (__p)
__ret = __p - __data;
}
return __ret;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
rfind(const _CharT* __s, size_type __pos, size_type __n) const
_GLIBCXX_NOEXCEPT
{
__glibcxx_requires_string_len(__s, __n);
const size_type __size = this->size();
if (__n <= __size)
{
__pos = std::min(size_type(__size - __n), __pos);
const _CharT* __data = _M_data();
do
{
if (traits_type::compare(__data + __pos, __s, __n) == 0)
return __pos;
}
while (__pos-- > 0);
}
return npos;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
rfind(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
{
size_type __size = this->size();
if (__size)
{
if (--__size > __pos)
__size = __pos;
for (++__size; __size-- > 0; )
if (traits_type::eq(_M_data()[__size], __c))
return __size;
}
return npos;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
_GLIBCXX_NOEXCEPT
{
__glibcxx_requires_string_len(__s, __n);
for (; __n && __pos < this->size(); ++__pos)
{
const _CharT* __p = traits_type::find(__s, __n, _M_data()[__pos]);
if (__p)
return __pos;
}
return npos;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
_GLIBCXX_NOEXCEPT
{
__glibcxx_requires_string_len(__s, __n);
size_type __size = this->size();
if (__size && __n)
{
if (--__size > __pos)
__size = __pos;
do
{
if (traits_type::find(__s, __n, _M_data()[__size]))
return __size;
}
while (__size-- != 0);
}
return npos;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
find_first_not_of(const _CharT* __s, size_type __pos, size_type __n) const
_GLIBCXX_NOEXCEPT
{
__glibcxx_requires_string_len(__s, __n);
for (; __pos < this->size(); ++__pos)
if (!traits_type::find(__s, __n, _M_data()[__pos]))
return __pos;
return npos;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
find_first_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
{
for (; __pos < this->size(); ++__pos)
if (!traits_type::eq(_M_data()[__pos], __c))
return __pos;
return npos;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
find_last_not_of(const _CharT* __s, size_type __pos, size_type __n) const
_GLIBCXX_NOEXCEPT
{
__glibcxx_requires_string_len(__s, __n);
size_type __size = this->size();
if (__size)
{
if (--__size > __pos)
__size = __pos;
do
{
if (!traits_type::find(__s, __n, _M_data()[__size]))
return __size;
}
while (__size--);
}
return npos;
}
template
typename basic_string<_CharT, _Traits, _Alloc>::size_type
basic_string<_CharT, _Traits, _Alloc>::
find_last_not_of(_CharT __c, size_type __pos) const _GLIBCXX_NOEXCEPT
{
size_type __size = this->size();
if (__size)
{
if (--__size > __pos)
__size = __pos;
do
{
if (!traits_type::eq(_M_data()[__size], __c))
return __size;
}
while (__size--);
}
return npos;
}
template
int
basic_string<_CharT, _Traits, _Alloc>::
compare(size_type __pos, size_type __n, const basic_string& __str) const
{
_M_check(__pos, "basic_string::compare");
__n = _M_limit(__pos, __n);
const size_type __osize = __str.size();
const size_type __len = std::min(__n, __osize);
int __r = traits_type::compare(_M_data() + __pos, __str.data(), __len);
if (!__r)
__r = _S_compare(__n, __osize);
return __r;
}
template
int
basic_string<_CharT, _Traits, _Alloc>::
compare(size_type __pos1, size_type __n1, const basic_string& __str,
size_type __pos2, size_type __n2) const
{
_M_check(__pos1, "basic_string::compare");
__str._M_check(__pos2, "basic_string::compare");
__n1 = _M_limit(__pos1, __n1);
__n2 = __str._M_limit(__pos2, __n2);
const size_type __len = std::min(__n1, __n2);
int __r = traits_type::compare(_M_data() + __pos1,
__str.data() + __pos2, __len);
if (!__r)
__r = _S_compare(__n1, __n2);
return __r;
}
template
int
basic_string<_CharT, _Traits, _Alloc>::
compare(const _CharT* __s) const _GLIBCXX_NOEXCEPT
{
__glibcxx_requires_string(__s);
const size_type __size = this->size();
const size_type __osize = traits_type::length(__s);
const size_type __len = std::min(__size, __osize);
int __r = traits_type::compare(_M_data(), __s, __len);
if (!__r)
__r = _S_compare(__size, __osize);
return __r;
}
template
int
basic_string <_CharT, _Traits, _Alloc>::
compare(size_type __pos, size_type __n1, const _CharT* __s) const
{
__glibcxx_requires_string(__s);
_M_check(__pos, "basic_string::compare");
__n1 = _M_limit(__pos, __n1);
const size_type __osize = traits_type::length(__s);
const size_type __len = std::min(__n1, __osize);
int __r = traits_type::compare(_M_data() + __pos, __s, __len);
if (!__r)
__r = _S_compare(__n1, __osize);
return __r;
}
template
int
basic_string <_CharT, _Traits, _Alloc>::
compare(size_type __pos, size_type __n1, const _CharT* __s,
size_type __n2) const
{
__glibcxx_requires_string_len(__s, __n2);
_M_check(__pos, "basic_string::compare");
__n1 = _M_limit(__pos, __n1);
const size_type __len = std::min(__n1, __n2);
int __r = traits_type::compare(_M_data() + __pos, __s, __len);
if (!__r)
__r = _S_compare(__n1, __n2);
return __r;
}
// 21.3.7.9 basic_string::getline and operators
template
basic_istream<_CharT, _Traits>&
operator>>(basic_istream<_CharT, _Traits>& __in,
basic_string<_CharT, _Traits, _Alloc>& __str)
{
typedef basic_istream<_CharT, _Traits> __istream_type;
typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
typedef typename __istream_type::ios_base __ios_base;
typedef typename __istream_type::int_type __int_type;
typedef typename __string_type::size_type __size_type;
typedef ctype<_CharT> __ctype_type;
typedef typename __ctype_type::ctype_base __ctype_base;
__size_type __extracted = 0;
typename __ios_base::iostate __err = __ios_base::goodbit;
typename __istream_type::sentry __cerb(__in, false);
if (__cerb)
{
__try
{
// Avoid reallocation for common case.
__str.erase();
_CharT __buf[128];
__size_type __len = 0;
const streamsize __w = __in.width();
const __size_type __n = __w > 0 ? static_cast<__size_type>(__w)
: __str.max_size();
const __ctype_type& __ct = use_facet<__ctype_type>(__in.getloc());
const __int_type __eof = _Traits::eof();
__int_type __c = __in.rdbuf()->sgetc();
while (__extracted < __n
&& !_Traits::eq_int_type(__c, __eof)
&& !__ct.is(__ctype_base::space,
_Traits::to_char_type(__c)))
{
if (__len == sizeof(__buf) / sizeof(_CharT))
{
__str.append(__buf, sizeof(__buf) / sizeof(_CharT));
__len = 0;
}
__buf[__len++] = _Traits::to_char_type(__c);
++__extracted;
__c = __in.rdbuf()->snextc();
}
__str.append(__buf, __len);
if (__extracted < __n && _Traits::eq_int_type(__c, __eof))
__err |= __ios_base::eofbit;
__in.width(0);
}
__catch(__cxxabiv1::__forced_unwind&)
{
__in._M_setstate(__ios_base::badbit);
__throw_exception_again;
}
__catch(...)
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 91. Description of operator>> and getline() for string<>
// might cause endless loop
__in._M_setstate(__ios_base::badbit);
}
}
// 211. operator>>(istream&, string&) doesn't set failbit
if (!__extracted)
__err |= __ios_base::failbit;
if (__err)
__in.setstate(__err);
return __in;
}
template
basic_istream<_CharT, _Traits>&
getline(basic_istream<_CharT, _Traits>& __in,
basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim)
{
typedef basic_istream<_CharT, _Traits> __istream_type;
typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
typedef typename __istream_type::ios_base __ios_base;
typedef typename __istream_type::int_type __int_type;
typedef typename __string_type::size_type __size_type;
__size_type __extracted = 0;
const __size_type __n = __str.max_size();
typename __ios_base::iostate __err = __ios_base::goodbit;
typename __istream_type::sentry __cerb(__in, true);
if (__cerb)
{
__try
{
__str.erase();
const __int_type __idelim = _Traits::to_int_type(__delim);
const __int_type __eof = _Traits::eof();
__int_type __c = __in.rdbuf()->sgetc();
while (__extracted < __n
&& !_Traits::eq_int_type(__c, __eof)
&& !_Traits::eq_int_type(__c, __idelim))
{
__str += _Traits::to_char_type(__c);
++__extracted;
__c = __in.rdbuf()->snextc();
}
if (_Traits::eq_int_type(__c, __eof))
__err |= __ios_base::eofbit;
else if (_Traits::eq_int_type(__c, __idelim))
{
++__extracted;
__in.rdbuf()->sbumpc();
}
else
__err |= __ios_base::failbit;
}
__catch(__cxxabiv1::__forced_unwind&)
{
__in._M_setstate(__ios_base::badbit);
__throw_exception_again;
}
__catch(...)
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 91. Description of operator>> and getline() for string<>
// might cause endless loop
__in._M_setstate(__ios_base::badbit);
}
}
if (!__extracted)
__err |= __ios_base::failbit;
if (__err)
__in.setstate(__err);
return __in;
}
// Inhibit implicit instantiations for required instantiations,
// which are defined via explicit instantiations elsewhere.
#if _GLIBCXX_EXTERN_TEMPLATE
// The explicit instantiation definitions in src/c++11/string-inst.cc and
// src/c++17/string-inst.cc only instantiate the members required for C++17
// and earlier standards (so not C++20's starts_with and ends_with).
// Suppress the explicit instantiation declarations for C++20, so C++20
// code will implicitly instantiate std::string and std::wstring as needed.
# if __cplusplus <= 201703L && _GLIBCXX_EXTERN_TEMPLATE > 0
extern template class basic_string;
# elif ! _GLIBCXX_USE_CXX11_ABI
// Still need to prevent implicit instantiation of the COW empty rep,
// to ensure the definition in libstdc++.so is unique (PR 86138).
extern template basic_string::size_type
basic_string::_Rep::_S_empty_rep_storage[];
# endif
extern template
basic_istream&
operator>>(basic_istream&, string&);
extern template
basic_ostream&
operator<<(basic_ostream&, const string&);
extern template
basic_istream&
getline(basic_istream&, string&, char);
extern template
basic_istream&
getline(basic_istream&, string&);
#ifdef _GLIBCXX_USE_WCHAR_T
# if __cplusplus <= 201703L && _GLIBCXX_EXTERN_TEMPLATE > 0
extern template class basic_string;
# elif ! _GLIBCXX_USE_CXX11_ABI
extern template basic_string::size_type
basic_string::_Rep::_S_empty_rep_storage[];
# endif
extern template
basic_istream&
operator>>(basic_istream&, wstring&);
extern template
basic_ostream&
operator<<(basic_ostream&, const wstring&);
extern template
basic_istream&
getline(basic_istream&, wstring&, wchar_t);
extern template
basic_istream&
getline(basic_istream&, wstring&);
#endif // _GLIBCXX_USE_WCHAR_T
#endif // _GLIBCXX_EXTERN_TEMPLATE
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif