no-throw-input-iterator, no-throw-forward-iterator, no-throw-sentinel-for, no-throw-input-range, no-throw-forward-range

 

C++

Compiler support

Freestanding and hosted

Language

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Technical specifications

Symbols index

External libraries

 

Utilities library

Language support Type support (basic types, RTTI, type traits)      Library feature-test macros (C++20) Dynamic memory management Program utilities Error handling Coroutine support (C++20) Variadic functions launder (C++17) initializer_list (C++11) source_location (C++20) Three-way comparison (C++20) three_way_comparablethree_way_comparable_with (C++20)(C++20) strong_ordering (C++20) weak_ordering (C++20) partial_ordering (C++20) common_comparison_category (C++20) compare_three_way_result (C++20) compare_three_way (C++20) strong_order (C++20) weak_order (C++20) partial_order (C++20) compare_strong_order_fallback (C++20) compare_weak_order_fallback (C++20) compare_partial_order_fallback (C++20) is_eqis_neqis_ltis_lteqis_gtis_gteq (C++20)(C++20)(C++20)(C++20)(C++20)(C++20)

General utilities Date and time Function objects bitset Formatting library (C++20) hash (C++11) integer_sequence (C++14) Relational operators (deprecated in C++20) rel_ops::operator!=rel_ops::operator> rel_ops::operator<=rel_ops::operator>= Integer comparison functions cmp_equalcmp_lesscmp_less_than (C++20)(C++20)(C++20)    cmp_not_equalcmp_greatercmp_greater_than (C++20)(C++20)(C++20) in_range (C++20) Swap and type operations swap ranges::swap (C++20) exchange (C++14) declval (C++11) forward (C++11) move (C++11) move_if_noexcept (C++11) as_const (C++17) to_underlying (C++23) Common vocabulary types pair tuple (C++11) optional (C++17) any (C++17) variant (C++17) tuple_size (C++11) tuple_element (C++11) apply (C++17) make_from_tuple (C++17) Elementary string conversions to_chars (C++17) from_chars (C++17) chars_format (C++17) Stacktrace stacktrace_entry (C++23) basic_stacktrace (C++23)

 

Dynamic memory management

Smart pointers unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (until C++17) owner_less (C++11) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) out_ptr_t (C++23) inout_ptr_t (C++23) Allocators allocator allocator_traits (C++11) allocation_result (C++23) allocate_at_least (C++23) allocator_arg_t (C++11) allocator_arg (C++11) uses_allocator (C++11) uses_allocator_construction_args (C++20) make_obj_using_allocator (C++20) uninitialized_construct_using_allocator (C++20) scoped_allocator_adaptor (C++11) pmr::polymorphic_allocator (C++17) Memory resources pmr::memory_resource (C++17) pmr::get_default_resource (C++17) pmr::set_default_resource (C++17) pmr::new_delete_resource (C++17) pmr::null_memory_resource (C++17) pmr::synchronized_pool_resource (C++17) pmr::unsynchronized_pool_resource (C++17) pmr::monotonic_buffer_resource (C++17) pmr::pool_options (C++17) Uninitialized storage raw_storage_iterator (until C++20) get_temporary_buffer (until C++20) return_temporary_buffer (until C++20)

Uninitialized memory algorithms uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) destroy_at (C++17) uninitialized_copy_n (C++11) uninitialized_fill_n uninitialized_move_n (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17) destroy_n (C++17) construct_at (C++20) Constrained uninitialized memory algorithms ranges::uninitialized_copy (C++20) ranges::uninitialized_fill (C++20) ranges::uninitialized_move (C++20) ranges::uninitialized_default_construct (C++20) ranges::uninitialized_value_construct (C++20) ranges::destroy (C++20) ranges::destroy_at (C++20) ranges::uninitialized_copy_n (C++20) ranges::uninitialized_fill_n (C++20) ranges::uninitialized_move_n (C++20) ranges::uninitialized_default_construct_n (C++20) ranges::uninitialized_value_construct_n (C++20) ranges::destroy_n (C++20) ranges::construct_at (C++20) Garbage collection support declare_reachable (C++11)(until C++23) undeclare_reachable (C++11)(until C++23) declare_no_pointers (C++11)(until C++23) undeclare_no_pointers (C++11)(until C++23) pointer_safety (C++11)(until C++23) get_pointer_safety (C++11)(until C++23) Miscellaneous pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) C Library malloc aligned_alloc (C++17) calloc realloc free Low level memory management operator new operator new[] operator delete operator delete[] get_new_handler set_new_handler bad_alloc bad_array_new_length nothrow_t align_val_t destroying_delete_t new_handler nothrow

 

Defined in header <memory>
template<class I> concept no-throw-input-iterator = // exposition only   std::input_iterator<I> &&   std::is_lvalue_reference_v<std::iter_reference_t<I>> &&   std::same_as<std::remove_cvref_t<std::iter_reference_t<I>>, std::iter_value_t<I>>;	(1)	(since C++20)
template<class I> concept no-throw-forward-iterator = // exposition only   no-throw-input-iterator<I> &&   std::forward_iterator<I> &&   no-throw-sentinel-for<I, I>;	(2)	(since C++20)
template<class S, class I> concept no-throw-sentinel-for = std::sentinel_for<S, I>; // exposition only	(3)	(since C++20)
template<class R> concept no-throw-input-range = // exposition only   ranges::range<R> &&   no-throw-input-iterator<ranges::iterator_t<R>> &&   no-throw-sentinel-for<ranges::sentinel_t<R>, ranges::iterator_t<R>>;	(4)	(since C++20)
template<class R> concept no-throw-forward-range = // exposition only   no-throw-input-range<R> &&   no-throw-forward-iterator<ranges::iterator_t<R>>;	(5)	(since C++20)

These exposition-only concepts specify that no exceptions are thrown from operations required by algorithms on iterators, sentinels, and ranges.

1) The no-throw-input-iterator concept requires that dereferencing the iterator yields an lvalue, like contiguous_iterator and LegacyForwardIterator.

Semantic requirements

Like all standard concepts, every concept listed here is modeled only if all concepts it subsumes are modeled.

1) A type I models no-throw-input-iterator only if no exceptions are thrown from increment, copy construction, move construction, copy assignment, move assignment, or indirection through valid iterators.

3) Types S and I model no-throw-sentinel-for only if no exceptions are thrown from copy construction, move construction, copy assignment, move assignment, or comparisons between valid values of type I and S.

4) A type R models no-throw-input-range only if no exceptions are thrown from calls to ranges::begin and ranges::end on an object of type R.

Notes

These concepts allow some operations on iterators and sentinels to throw exceptions, e.g. operations on invalid values.

See also

input_iterator (C++20)	specifies that a type is an input iterator, that is, its referenced values can be read and it can be both pre- and post-incremented (concept)
forward_iterator (C++20)	specifies that an input_iterator is a forward iterator, supporting equality comparison and multi-pass (concept)
sentinel_for (C++20)	specifies a type is a sentinel for an input_or_output_iterator type (concept)
ranges::input_range (C++20)	specifies a range whose iterator type satisfies input_iterator (concept)
ranges::forward_range (C++20)	specifies a range whose iterator type satisfies forward_iterator (concept)