C++ named requirements: FormattedInputFunction
Requirements
A FormattedInputFunction is a stream input function that performs the following:
- Constructs an object of type
basic_istream::sentry
with automatic storage duration and with thenoskipws
argument set tofalse
, which performs the following - if
eofbit
orbadbit
are set on the input stream, sets thefailbit
as well, and if exceptions on failbit are enabled in this input stream's exception mask, throwsios_base::failure
. - flushes the tie()'d output stream, if applicable
- if
ios_base::skipws
flag is set on this input stream, extracts and discards characters from the input stream until one of the following becomes true: - the next available character on the input stream is not a whitespace character, as tested by the
std::ctype
facet of the locale currently imbued in this input stream. The non-whitespace character is not extracted. - the end of the stream is reached, in which case
failbit
andeofbit
are set and if the stream is on for exceptions on one of these bits,ios_base::failure
is thrown. - Checks the status of the sentry by calling
sentry::operator bool()
, which is equivalent tobasic_ios::good
. - If the sentry returned
false
or sentry's constructor threw an exception, no input takes place - If the sentry returned
true
, performs the input as if by callingrdbuf()->sbumpc()
orrdbuf()->sgetc()
. - if the end of the stream is reached (the call to
rdbuf()->sbumpc()
orrdbuf()->sgetc()
returnsTraits::eof()
), setseofbit
. If exceptions on eofbit are enabled in this stream's exception mask, throwsios_base::failure
. - if an exception is thrown during input, sets
badbit
in the input stream. If exceptions on badbit are enabled in this stream's exception mask, the exception is also rethrown. - If no exception was thrown, returns
*this
. - In any event, whether terminating by exception or returning, the sentry's destructor is called before leaving this function.
Standard library
The following standard library functions are FormattedInputFunctions.
-
basic_istream::operator>>(int, long, double, void*, bool)
-
operator>>(std::basic_istream, char&)
-
operator>>(std::basic_istream, char*)
-
operator>>(std::basic_istream, std::bitset)
-
operator>>(std::basic_istream, std::string)
-
operator>>
, when called on the return value ofstd::get_money
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