std::operator+(std::basic_string)

 

C++

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Symbols index

External libraries

 

Strings library

Null-terminated strings

Byte strings

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Classes

basic_string

basic_string_view (C++17)

char_traits

 

std::basic_string

Member functions basic_string::basic_string basic_string::~basic_string basic_string::operator= basic_string::assign basic_string::assign_range (C++23) basic_string::get_allocator Element access basic_string::at basic_string::operator[] basic_string::front (DR*) basic_string::back (DR*) basic_string::data basic_string::c_str basic_string::operator  basic_string_view (C++17) Iterators basic_string::beginbasic_string::cbegin (C++11) basic_string::endbasic_string::cend (C++11) basic_string::rbeginbasic_string::crbegin (C++11) basic_string::rendbasic_string::crend (C++11) Capacity basic_string::empty basic_string::sizebasic_string::length basic_string::max_size basic_string::reserve basic_string::capacity basic_string::shrink_to_fit (DR*) Modifiers basic_string::clear basic_string::insert basic_string::insert_range (C++23) basic_string::erase basic_string::push_back basic_string::pop_back (DR*) basic_string::append basic_string::append_range (C++23) basic_string::operator+= basic_string::replace basic_string::replace_with_range (C++23) basic_string::copy basic_string::resize basic_string::resize_and_overwrite (C++23)   basic_string::swap

Search basic_string::find basic_string::rfind basic_string::find_first_of basic_string::find_first_not_of basic_string::find_last_of basic_string::find_last_not_of Operations basic_string::compare basic_string::starts_with (C++20) basic_string::ends_with (C++20) basic_string::contains (C++23) basic_string::substr Constants basic_string::npos Non-member functions operator+ swap(std::basic_string) erase(std::basic_string)erase_if(std::basic_string) (C++20)(C++20) I/O operator<<operator>> getline Comparison operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20) Numeric conversions stoistolstoll (C++11)(C++11)(C++11) stoulstoull (C++11)(C++11) stofstodstold (C++11)(C++11)(C++11) to_string (C++11) to_wstring (C++11) Literals operator""s (C++14) Helper classes hash<std::basic_string> (C++11) Deduction guides (C++17)

 

Template:ddcl list begin <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( const basic_string<CharT,Traits,Alloc>& lhs,

                   const basic_string<CharT,Traits,Alloc>& rhs );

</td>

<td > (1) </td> <td class="t-dcl-nopad"> </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( const CharT* lhs,

                   const basic_string<CharT,Traits,Alloc>& rhs );

</td>

<td > (2) </td> <td class="t-dcl-nopad"> </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( CharT lhs,

                   const basic_string<CharT,Traits,Alloc>& rhs );

</td>

<td > (3) </td> <td class="t-dcl-nopad"> </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( const basic_string<CharT,Traits,Alloc>& lhs,

                   const CharT* rhs );

</td>

<td > (4) </td> <td class="t-dcl-nopad"> </td> </tr> <tr class="t-dcl ">

<td >

template<class CharT, class Traits, class Alloc>

    basic_string<CharT,Traits,Alloc>
        operator+( const basic_string<CharT,Traits,Alloc>& lhs,

                   CharT rhs );

</td>

<td > (5) </td> <td class="t-dcl-nopad"> </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( basic_string<CharT,Traits,Alloc>&& lhs,

                   const basic_string<CharT,Traits,Alloc>& rhs );

</td>

<td > (6) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( const basic_string<CharT,Traits,Alloc>& lhs,

                   basic_string<CharT,Traits,Alloc>&& rhs );

</td>

<td > (7) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( basic_string<CharT,Traits,Alloc>&& lhs,

                   basic_string<CharT,Traits,Alloc>&& rhs );

</td>

<td > (8) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+(const CharT* lhs,

                  basic_string<CharT,Traits,Alloc>&& rhs );

</td>

<td > (9) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( CharT lhs,

                   basic_string<CharT,Traits,Alloc>&& rhs );

</td>

<td > (10) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( basic_string<CharT,Traits,Alloc>&& lhs,

                   const CharT* rhs );

</td>

<td > (11) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">

<td >

template< class CharT, class Traits, class Alloc >

    basic_string<CharT,Traits,Alloc>
        operator+( basic_string<CharT,Traits,Alloc>&& lhs,

                   CharT rhs );

</td>

<td > (12) </td> <td > (since C++11) </td> </tr> Template:ddcl list end

Returns a string containing characters from lhs followed by the characters from rhs.

Parameters

lhs	-	string, character, or pointer to the first character in a null-terminated array
rhs	-	string, character, or pointer to the first character in a null-terminated array

Return value

1) basic_string<CharT,Traits,Alloc>(lhs).append(rhs)

2) basic_string<CharT,Traits,Alloc>(lhs) + rhs

3) basic_string<CharT,Traits,Alloc>(1,lhs) + rhs

4) lhs + basic_string<CharT,Traits,Alloc>(rhs)

5) lhs + basic_string<CharT,Traits,Alloc>(1,rhs)

6) std::move(lhs.append(rhs))

7) std::move(rhs.insert(0, lhs))

8) std::move(lhs.append(rhs)) or std::move(rhs.insert(0, lhs))

9) std::move(rhs.insert(0, lhs))

10) std::move(rhs.insert(0, 1, lhs))

11) std::move(lhs.append(rhs))

12) std::move(lhs.append(1, rhs))

Example

Run this code

#include <iostream>
#include <string>
 
int main()
{
    std::string s1 = "Hello";
    std::string s2 = "world";
    std::cout << s1 + ' ' + s2 + "!\n";
}

Output:

Hello world!

See also

Template:cpp/string/basic string/dcl list operator+=Template:cpp/string/basic string/dcl list appendTemplate:cpp/string/basic string/dcl list insert