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<ostream> operators

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operator<<

operator<<

Writes various types to the stream.

template <class _Elem, class _Tr>
basic_ostream<_Elem, _Tr>& operator<<(
    basic_ostream<_Elem, _Tr>& _Ostr,
    const Elem* str);

template <class _Elem, class _Tr>
basic_ostream<_Elem, _Tr>& operator<<(
    basic_ostream<_Elem, _Tr>& _Ostr,
    Elem _Ch);

template <class _Elem, class _Tr>
basic_ostream<_Elem, _Tr>& operator<<(
    basic_ostream<_Elem, _Tr>& _Ostr,
    const char* str);

template <class _Elem, class _Tr>
basic_ostream<_Elem, _Tr>& operator<<(
    basic_ostream<_Elem, _Tr>& _Ostr,
    char _Ch);

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    const char* str);

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _ostr,
    char _Ch);

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    const signed char* str);

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    signed char _Ch);

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    const unsigned char* str);

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    unsigned char _Ch);

template <class _Elem, class _Tr, class T>
basic_ostream <_Elem, _Tr>& operator<<(
    basic_ostream<_Elem, _Tr>&& _Ostr,
    Ty val);

Parameters

_Ch
A character.

_Elem
The element type.

_Ostr
A basic_ostream object.

str
A character string.

_Tr
Character traits.

val
The type

Return Value

The stream.

Remarks

The basic_ostream class also defines several insertion operators. For more information, see basic_ostream::operator<<.

The template function

template <class _Elem, class _Tr>
basic_ostream<Elem, _Tr>& operator<<(
    basic_ostream<Elem, _Tr>& _ostr,
    const Elem *str);

determines the length N = traits_type::length(str) of the sequence beginning at str, and inserts the sequence. If N < _Ostr.width, then the function also inserts a repetition of _Ostr.width - N fill characters. The repetition precedes the sequence if (_Ostr. flags & adjustfield != left. Otherwise, the repetition follows the sequence. The function returns _Ostr.

The template function

template <class _Elem, class _Tr>
basic_ostream<Elem, _Tr>& operator<<(
    basic_ostream<Elem, _Tr>& _Ostr,
    Elem _Ch);

inserts the element _Ch. If 1 < _Ostr.width, then the function also inserts a repetition of _Ostr.width - 1 fill characters. The repetition precedes the sequence if _Ostr.flags & adjustfield != left. Otherwise, the repetition follows the sequence. It returns _Ostr.

The template function

template <class _Elem, class _Tr>
basic_ostream<Elem, _Tr>& operator<<(
    basic_ostream<Elem, _Tr>& _Ostr,
    const char *str);

behaves the same as

template <class _Elem, class _Tr>
basic_ostream<Elem, _Tr>& operator<<(
    basic_ostream<Elem, _Tr>& _Ostr,
    const Elem *str);

except that each element _Ch of the sequence beginning at str is converted to an object of type Elem by calling _Ostr.put(_Ostr.widen(_Ch)).

The template function

template <class _Elem, class _Tr>
basic_ostream<Elem, _Tr>& operator<<(
    basic_ostream<Elem, _Tr>& _Ostr,
    char _Ch);

behaves the same as

template <class _Elem, class _Tr>
basic_ostream<Elem, _Tr>& operator<<(
    basic_ostream<Elem, _Tr>& _Ostr,
    Elem _Ch);

except that _Ch is converted to an object of type Elem by calling _Ostr.put( _Ostr.widen( _Ch )).

The template function

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    const char *str);

behaves the same as

template <class _Elem, class _Tr>
basic_ostream<Elem, _Tr>& operator<<(
    basic_ostream<Elem, _Tr>& _Ostr,
    const Elem *str);

(It does not have to widen the elements before inserting them.)

The template function

template <class _Tr>
basic_ostream<char, Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    char _Ch);

behaves the same as

template <class _Elem, class _Tr>
basic_ostream<Elem, _Tr>& operator<<(
    basic_ostream<Elem, _Tr>& _Ostr,
    Elem _Ch);

(It does not have to widen _Ch before inserting it.)

The template function

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    const signed char *str);

returns _Ostr << (const char *)str.

The template function

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    signed char _Ch);

returns _Ostr << (char)_Ch.

The template function:

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    const unsigned char *str);

returns _Ostr << (const char *)str.

The template function:

template <class _Tr>
basic_ostream<char, _Tr>& operator<<(
    basic_ostream<char, _Tr>& _Ostr,
    unsigned char _Ch);

returns _Ostr << (char)_Ch.

The template function:

template <class _Elem, class _Tr, class T>
basic_ostream<_Elem, _Tr>& operator<<(
    basic_ostream<char, _Tr>&& _Ostr,
    T val);

returns _Ostr << val (and converts a RValue Reference to _Ostr to an lvalue in the process).

Example

See flush for an example using operator<<.

See also

<ostream>