C++ concepts: ConstexprIterator

 

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A ConstexprIterator is an Iterator that can be used during constant expression evaluation.

Requirements

The type It satisfies ConstexprIterator if

• The type It satisfies some iterator concept MeowIterator

And, for every

• purr, an operation on It that is required to be supported by MeowIterator,
• kittens..., a set of arguments to purr that meets the requirements for that operation,

Then

• purr(kittens...) may be used in a constant expression if kittens... can be so used, unless purr is

• a call to swap;
• construction of It with a singular value;
• an explicit destructor call (if It is a class type); or
• a pseudo-destructor call (if It is a scalar type)

Standard library

The following standard library types are ConstexprIterators.

• array::iterator.
• basic_string_view::iterator.

See also

• Iterator library