28 Text processing library [text]

The classes num_get<> and num_put<> handle numeric formatting and parsing.

Virtual functions are provided for several numeric types.

Implementations may (but are not required to) delegate extraction of smaller types to extractors for larger types.²⁰²

All specifications of member functions for num_put and num_get in the subclauses of [category.numeric] only apply to the specializations required in Tables 91 and 92 ([locale.category]), namely num_get<char>, num_get<wchar_t>, num_get<C, InputIterator>, num_put<char>, num_put<wchar_t>, and num_put<C, OutputIterator>.

These specializations refer to the ios_base& argument for formatting specifications ([locale.categories]), and to its imbued locale for the numpunct<> facet to identify all numeric punctuation preferences, and also for the ctype<> facet to perform character classification.

Extractor and inserter members of the standard iostreams use num_get<> and num_put<> member functions for formatting and parsing numeric values ([istream.formatted.reqmts], [ostream.formatted.reqmts]).