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# std::basic_string::basic_string

From cppreference.com
< cpp‎ | string‎ | basic string

explicit basic_string( const Allocator& alloc = Allocator() ); | (1) |
basic_string( size_type count, CharT ch, const Allocator& alloc = Allocator() ); | (2) |
basic_string( const basic_string& other, size_type pos, size_type count = std::basic_string::npos, const Allocator& alloc = Allocator() ); | (3) |
basic_string( const CharT* s, size_type count, const Allocator& alloc = Allocator() ); | (4) |
basic_string( const CharT* s, const Allocator& alloc = Allocator() ); | (5) |
template< class InputIt > basic_string( InputIt first, InputIt last, const Allocator& alloc = Allocator() ); | (6) |
basic_string( const basic_string& other ); | (7) |
basic_string( const basic_string& other, const Allocator& alloc ); | (7) | (since C++11)
basic_string( basic_string&& other ) | (8) | (since C++11)
basic_string( basic_string&& other, const Allocator& alloc ); | (8) | (since C++11)
basic_string( std::initializer_list<CharT> init, const Allocator& alloc = Allocator() ); | (9) | (since C++11)

Constructs new string from a variety of data sources and optionally using user supplied allocator `alloc`.

1) Default constructor. Constructs empty string.
2) Constructs the string with `count` copies of character `ch`.
3) Constructs the string with a substring `[pos, pos+count)` of `other`. If the requested substring lasts past the end of the string, or if count == npos, the resulting substring is `[pos, size())`. If pos >= other.size(), std::out_of_range is thrown.
4) Constructs the string with the first `count` characters of character string pointed to by `s`. `s` can contain null characters. The behavior is undefined if `s` does not point at an array of at least `count` elements of `CharT`.
5) Constructs the string with the contents initialized with a copy of the null-terminated character string pointed to by `s`. The length of the string is determined by the first null character. The behavior is undefined if `s` does not point at an array of at least Traits::length(s)+1 elements of `CharT`.
6) Constructs the string with the contents of the range `[first, last)`.
7) Copy constructor. Constructs the string with the copy of the contents of `other`.
8) Move constructor. Constructs the string with the contents of `other` using move semantics.
9) Constructs the string with the contents of the initializer list `init`.

### [edit] Parameters

alloc | - | allocator to use for all memory allocations of this string
count | - | size of the resulting string
ch | - | value to initialize the string with
first, last | - | range to copy the characters from
s | - | pointer to a character string to use as source to initialize the string with
other | - | another string to use as source to initialize the string with
init | - | initializer list to initialize the string with
Type requirements
- `InputIt` must meet the requirements of `InputIterator`.

### [edit] Complexity

1) constant

2-4) linear in `count`

5) linear in length of `s`

6) linear in distance between `first` and `last`

7) linear in size of `other`

8) constant. If `alloc` is given and alloc != other.get_allocator(), then linear.

9) linear in size of `init`

### [edit] Example

| This section is incomplete Reason: no example

### [edit] See also

assign | assign characters to a string (public member function) [edit]
operator= | assigns values to the string (public member function) [edit]

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