From cppreference.com
Defined in header
Call signature
template</*nothrow-input-iterator*/I,/*nothrow-sentinel-for*/<I>S>requiresstd::destructible<std::iter_value_t<I>>constexprIdestroy(Ifirst,Slast)noexcept; (1) (since C++20)template</*nothrow-input-range*/R>requiresstd::destructible<ranges::range_value_t<R>>constexprranges::borrowed_iterator_t<R>destroy(R&&r)noexcept; (2) (since C++20)template</*execution-policy*/Ep,/*nothrow-random-access-iterator*/I,/*nothrow-sized-sentinel-for*/<I>S>requiresstd::destructible<std::iter_value_t<I>>Idestroy(Ep&&policy,Ifirst,Slast); (3) (since C++26)template</*execution-policy*/Ep,/*nothrow-sized-random-access-range*/R>requiresstd::destructible<ranges::range_value_t<R>>ranges::borrowed_iterator_t<R>destroy(Ep&&policy,R&&r); (4) (since C++26)For the definition of /*execution-policy*/, see
; for the definition of other exposition-only concepts, see
.
1) Destroys elements in the target range [first, last) as if by
for(;first!=last;++first)std::ranges::destroy_at(std::addressof(*first));returnfirst;2) Same as (1), but uses r as the target range.
3,4) Same as (1,2), but executed according to policy.
The function-like entities described on this page are
(informally known as niebloids), that is:
Explicit template argument lists cannot be specified when calling any of them.
None of them are visible to
.
When any of them are found by
as the name to the left of the function-call operator,
is inhibited.
Parameters
first, last - the iterator-sentinel pair defining the
of elements to destroy r - the
to destroy policy - the
to use Return value
As described above.
Exceptions
3,4) During the execution process:
If the temporary memory resources required for parallelization are not available,
is thrown.
If an uncaught exception is thrown while accessing objects via an algorithm argument, the behavior is determined by the execution policy (for
,
is invoked).
Notes
macro ValueStdFeature
(C++26)Parallel range algorithms Possible implementation
structdestroy_fn{template</*nothrow-input-iterator*/I,/*nothrow-sentinel-for*/<I>S>requiresstd::destructible<std::iter_value_t<I>>constexprIoperator()(Ifirst,Slast)constnoexcept{for(;first!=last;++first)ranges::destroy_at(std::addressof(*first));returnfirst;}template</*nothrow-input-range*/R>requiresstd::destructible<ranges::range_value_t<R>>constexprranges::borrowed_iterator_t<R>operator()(R&&r)constnoexcept{return(*this)(ranges::begin(r),ranges::end(r));}template</*nothrow-forward-range*/R>requiresstd::destructible<ranges::range_value_t<R>>constexprranges::borrowed_iterator_t<R>operator()(R&&r)constnoexcept{return(*this)(ranges::begin(r),ranges::next(ranges::begin(r),ranges::end(r)));}};inlineconstexprdestroy_fndestroy{};Example
Demonstrates how to use ranges::destroy to destroy a contiguous sequence of elements.
Run this code
#include<iostream>#include<memory>#include<new>structTracer{intvalue;~Tracer(){std::cout<<value<<" destructed\n";}};intmain(){alignas(Tracer)unsignedcharbuffer[sizeof(Tracer)*4];for(inti=0;i<4;++i)new(buffer+sizeof(Tracer)*i)Tracer{i};// manually construct objectsautoptr=std::launder(reinterpret_cast<Tracer*>(buffer));std::ranges::destroy(ptr,ptr+4);}Output:
0 destructed 1 destructed 2 destructed 3 destructed See also