std::default_constructible

 

C++

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Concepts library (C++20)

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Technical Specifications

 

Concepts library

Core language concepts
same_as derived_from convertible_to common_reference_with common_with	integral signed_integral unsigned_integral floating_point swappableswappable_with	destructible constructible_from default_constructible move_constructible copy_constructible assignable_from
Comparison concepts
boolean	equality_comparableequality_comparable_with	totally_orderedtotally_ordered_with
Object concepts
movable copyable	semiregular regular
Callable concepts
invocableregular_invocable	predicate	relation strict_weak_order

 

Defined in header <concepts>
template < class T > concept default_constructible = std::constructible_from<T>;		(since C++20)

The default_constructible concept provides a shorthand for the common case when the question is whether a type can be constructed with no arguments.

See also

constructible_from (C++20)	specifies that a variable of the type can be constructed from or bound to a set of argument types (concept)
is_default_constructibleis_trivially_default_constructibleis_nothrow_default_constructible (C++11)(C++11)(C++11)	checks if a type has a default constructor (class template)