std::match_results<BidirIt,Alloc>::empty - cppreference.com (original) (raw)

C++

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Text processing library

Localization library
Regular expressions library (C++11)
Formatting library (C++20)
Null-terminated sequence utilities
Byte strings
Multibyte strings
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Primitive numeric conversions
to_chars(C++17) to_chars_result(C++17) from_chars(C++17) from_chars_result(C++17) chars_format(C++17)
Text encoding identifications
text_encoding(C++26)

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Regular expressions library

Classes
basic_regex(C++11)
sub_match(C++11)
match_results(C++11)
Algorithms
regex_match(C++11)
regex_search(C++11)
regex_replace(C++11)
Iterators
regex_iterator(C++11)
regex_token_iterator(C++11)
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regex_error(C++11)
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regex_traits(C++11)
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syntax_option_type(C++11)
match_flag_type(C++11)
error_type(C++11)
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Modified ECMAScript-262(C++11)

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std::match_results

Member functions
match_results::match_results
match_results::~match_results
match_results::operator=
match_results::get_allocator
State
match_results::ready
Element access
match_results::size
match_results::max_size
match_results::empty
match_results::length
match_results::position
match_results::str
match_results::operator[]
match_results::prefix
match_results::suffix
Iterators
match_results::beginmatch_results::cbegin
match_results::endmatch_results::cend
Format
match_results::format
Modifiers
match_results::swap
Non-member functions
operator==operator!=(until C++20)
swap(std::match_results)

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| bool empty() const; | | (since C++11) | | ------------------- | | ------------- |

Checks whether the match was successful.

Contents

[edit] Parameters

(none)

[edit] Return value

true if *this represents the result of a failed match, false otherwise, i.e. size() == 0.

[edit] Exceptions

May throw implementation-defined exceptions.

[edit] Complexity

Constant.

[edit] See also

size returns the number of matches in a fully-established result state (public member function) [edit]