std::match_results<BidirIt,Alloc>::match_results
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                    < cpp | regex | match results
                    
                                                            
                    | match_results() : match_results(Allocator()) { } | (1) | (since C++11) | 
| explicit match_results( const Allocator& a ); | (2) | (since C++11) | 
| match_results( const match_results& rhs ); | (3) | (since C++11) | 
| match_results( match_results&& rhs ) noexcept; | (4) | (since C++11) | 
1) Default-constructor. Constructs a match result with no established result state (ready() != true).
2) Constructs a match result with no established result state (ready() != true) using a copy of 
a as the allocator.3) Copy-constructor. Constructs a match result with a copy of 
rhs.4) Move-constructor. Constructs a match result with the contents of 
rhs using move semantics. rhs is in valid, but unspecified state after the call.Parameters
| a | - | allocator to use for all memory allocations of this container | 
| rhs | - | another match_result to use as source to initialize the match_result with | 
Exceptions
1-2) (none)
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior | 
|---|---|---|---|
| P0935R0 | C++11 | default constructor was explicit | made implicit |