std::basic_regex(3)

NAME
std::basic_regex - std::basic_regex

Synopsis
   Defined in header <regex>
   template<
       class CharT, (since C++11)
       class Traits = std::regex_traits<CharT>
   > class basic_regex;
   The class template basic_regex provides a general framework for holding regular
   expressions.
   Several typedefs for common character types are provided:
   Defined in header <regex>
   Type Definition
   std::regex std::basic_regex<char>
   std::wregex std::basic_regex<wchar_t>

Member types
   Member type Definition
   value_type CharT
   traits_type Traits
   string_type Traits::string_type
   locale_type Traits::locale_type
   flag_type std::regex_constants::syntax_option_type

Member functions
   constructor constructs the regex object
                 (public member function)
   destructor destructs the regex object
                 (public member function)
   operator= assigns the contents
                 (public member function)
   assign assigns the contents
                 (public member function)

Observers
                 returns the number of marked sub-expressions within the regular
   mark_count expression
                 (public member function)
   flags returns the syntax flags
                 (public member function)

Locale
   getloc get locale information
                 (public member function)
   imbue set locale information
                 (public member function)

Modifiers
   swap swaps the contents
                 (public member function)

Constants
   Grammar option Effect(s)
   ECMAScript Use the Modified ECMAScript regular expression grammar.
   basic Use the basic POSIX regular expression grammar (grammar
                     documentation).
   extended Use the extended POSIX regular expression grammar (grammar
                     documentation).
   awk Use the regular expression grammar used by the awk utility in
                     POSIX (grammar documentation).
                     Use the regular expression grammar used by the grep utility in
   grep POSIX. This is effectively the same as the basic option with the
                     addition of newline '\n' as an alternation separator.
                     Use the regular expression grammar used by the grep utility, with
   egrep the -E option, in POSIX. This is effectively the same as the
                     extended option with the addition of newline '\n' as an
                     alternation separator in addition to '|'.
   Grammar variation Effect(s)
   icase Character matching should be performed without regard to case.
                     When performing matches, all marked sub-expressions (expr) are
   nosubs treated as non-marking sub-expressions (?:expr). No matches are
                     stored in the supplied std::regex_match structure and mark_count()
                     is zero.
                     Instructs the regular expression engine to make matching faster,
   optimize with the potential cost of making construction slower. For
                     example, this might mean converting a non-deterministic FSA to a
                     deterministic FSA.
   collate Character ranges of the form "[a-b]" will be locale sensitive.
   multiline (C++17) Specifies that ^ shall match the beginning of a line and $ shall
                     match the end of a line, if the ECMAScript engine is selected.
   At most one grammar option can be chosen out of ECMAScript, basic, extended, awk,
   grep, egrep. If no grammar is chosen, ECMAScript is assumed to be selected. The
   other options serve as variations, such that std::regex("meow", std::regex::icase)
   is equivalent to std::regex("meow", std::regex::ECMAScript|std::regex::icase).
   The member constants in basic_regex are duplicates of the syntax_option_type
   constants defined in the namespace std::regex_constants.

Non-member functions
   std::swap(std::basic_regex) specializes the std::swap algorithm
   (C++11) (function template)
   Deduction guides(since C++17)