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std::basic_ispanstream

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< cpp‎ | io
 
C++
 
Input/output library
 
std::basic_ispanstream
 
Defined in header <spanstream>
template<

    class CharT,
    class Traits = std::char_traits<CharT>
> class basic_ispanstream

    : public basic_istream<CharT, Traits>
 (since C++23)

The class template std::basic_ispanstream implements input operations on streams based on fixed buffers.

At the low level, the class essentially wraps a raw device implementation of std::basic_spanbuf into a higher-level interface of std::basic_istream. The complete interface to unique std::basic_spanbuf members is provided.

cpp/io/ios basecpp/io/basic ioscpp/io/basic istreamstd-basic ispanstream-inheritance.svg

Inheritance diagram

Several typedefs for common character types are provided:

Defined in header <spanstream>
Type Definition
std::ispanstream std::basic_ispanstream<char>
std::wispanstream std::basic_ispanstream<wchar_t>

Contents

[edit] Member types

Member type Definition
char_type CharT[edit]
traits_type Traits; the program is ill-formed if Traits::char_type is not CharT.[edit]
int_type Traits::int_type[edit]
pos_type Traits::pos_type[edit]
off_type Traits::off_type[edit]

[edit] Data members

Member object Definition
sb (private) The wrapped std::basic_spanbuf.
(exposition-only member object*)

[edit] Member functions

 constructs the basic_ispanstream
(public member function) [edit]
(destructor)
[virtual]
 destroys the basic_ispanstream
(virtual public member function)
move-assignments the basic_ispanstream
(public member function) [edit]
swaps two basic_ispanstream objects
(public member function) [edit]
obtains the address of the wrapped raw span device object
(public member function) [edit]
Underlying buffer operations
gets or sets the underlying buffer of the wrapped span device object
(public member function) [edit]

[edit] Non-member functions

(C++23)
 specializes the std::swap algorithm
(function template) [edit]

Inherited from std::basic_istream

Member functions

Formatted input
extracts formatted data
(public member function of std::basic_istream<CharT,Traits>) [edit]
Unformatted input
extracts characters
(public member function of std::basic_istream<CharT,Traits>) [edit]
reads the next character without extracting it
(public member function of std::basic_istream<CharT,Traits>) [edit]
unextracts a character
(public member function of std::basic_istream<CharT,Traits>) [edit]
puts a character into input stream
(public member function of std::basic_istream<CharT,Traits>) [edit]
extracts characters until the given character is found
(public member function of std::basic_istream<CharT,Traits>) [edit]
extracts and discards characters until the given character is found
(public member function of std::basic_istream<CharT,Traits>) [edit]
extracts blocks of characters
(public member function of std::basic_istream<CharT,Traits>) [edit]
extracts already available blocks of characters
(public member function of std::basic_istream<CharT,Traits>) [edit]
returns number of characters extracted by last unformatted input operation
(public member function of std::basic_istream<CharT,Traits>) [edit]
Positioning
returns the input position indicator
(public member function of std::basic_istream<CharT,Traits>) [edit]
sets the input position indicator
(public member function of std::basic_istream<CharT,Traits>) [edit]
Miscellaneous
synchronizes with the underlying storage device
(public member function of std::basic_istream<CharT,Traits>) [edit]

Member classes

 implements basic logic for preparation of the stream for input operations
(public member class of std::basic_istream<CharT,Traits>) [edit]

Inherited from std::basic_ios

Member types

Member type Definition
char_type CharT
traits_type Traits
int_type Traits::int_type
pos_type Traits::pos_type
off_type Traits::off_type

Member functions

State functions
checks if no error has occurred i.e. I/O operations are available
(public member function of std::basic_ios<CharT,Traits>) [edit]
checks if end-of-file has been reached
(public member function of std::basic_ios<CharT,Traits>) [edit]
checks if an error has occurred
(public member function of std::basic_ios<CharT,Traits>) [edit]
checks if a non-recoverable error has occurred
(public member function of std::basic_ios<CharT,Traits>) [edit]
checks if an error has occurred (synonym of fail())
(public member function of std::basic_ios<CharT,Traits>) [edit]
checks if no error has occurred (synonym of !fail())
(public member function of std::basic_ios<CharT,Traits>) [edit]
returns state flags
(public member function of std::basic_ios<CharT,Traits>) [edit]
sets state flags
(public member function of std::basic_ios<CharT,Traits>) [edit]
modifies state flags
(public member function of std::basic_ios<CharT,Traits>) [edit]
Formatting
copies formatting information
(public member function of std::basic_ios<CharT,Traits>) [edit]
manages the fill character
(public member function of std::basic_ios<CharT,Traits>) [edit]
Miscellaneous
manages exception mask
(public member function of std::basic_ios<CharT,Traits>) [edit]
sets the locale
(public member function of std::basic_ios<CharT,Traits>) [edit]
manages associated stream buffer
(public member function of std::basic_ios<CharT,Traits>) [edit]
manages tied stream
(public member function of std::basic_ios<CharT,Traits>) [edit]
narrows characters
(public member function of std::basic_ios<CharT,Traits>) [edit]
widens characters
(public member function of std::basic_ios<CharT,Traits>) [edit]

Inherited from std::ios_base

Member functions

Formatting
manages format flags
(public member function of std::ios_base) [edit]
sets specific format flag
(public member function of std::ios_base) [edit]
clears specific format flag
(public member function of std::ios_base) [edit]
manages decimal precision of floating point operations
(public member function of std::ios_base) [edit]
manages field width
(public member function of std::ios_base) [edit]
Locales
sets locale
(public member function of std::ios_base) [edit]
returns current locale
(public member function of std::ios_base) [edit]
Internal extensible array
[static]
 returns a program-wide unique integer that is safe to use as index to pword() and iword()
(public static member function of std::ios_base) [edit]
resizes the private storage if necessary and access to the long element at the given index
(public member function of std::ios_base) [edit]
resizes the private storage if necessary and access to the void* element at the given index
(public member function of std::ios_base) [edit]
Miscellaneous
registers event callback function
(public member function of std::ios_base) [edit]
[static]
 sets whether C++ and C I/O libraries are interoperable
(public static member function of std::ios_base) [edit]
Member classes
stream exception
(public member class of std::ios_base) [edit]
initializes standard stream objects
(public member class of std::ios_base) [edit]

Member types and constants

Type Explanation
stream open mode type

The following constants are also defined:

Constant Explanation[edit]
app seek to the end of stream before each write[edit]
binary open in binary mode[edit]
in open for reading[edit]
out open for writing[edit]
trunc discard the contents of the stream when opening[edit]
ate seek to the end of stream immediately after open[edit]
noreplace (C++23) open in exclusive mode[edit]

(typedef) [edit]
formatting flags type

The following constants are also defined:

Constant Explanation[edit]
dec use decimal base for integer I/O: see std::dec[edit]
oct use octal base for integer I/O: see std::oct[edit]
hex use hexadecimal base for integer I/O: see std::hex[edit]
basefield dec | oct | hex. Useful for masking operations[edit]
left left adjustment (adds fill characters to the right): see std::left