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Associated Characteristics and Associators

An asynchronous agent has associated characteristics that specify how asynchronous operations should behave when composed as part of that agent, such as:

When an asynchronous operation is run within an asynchronous agent, its implementation may query these associated characteristics and use them to satisfy the requirements or preferences they represent. The asynchronous operation performs these queries by applying associator traits to the completion handler. Each characteristic has a corresponding associator trait.

An associator trait may be specialised for concrete completion handler types to:

Specification of an Associator

Given an associator trait named[2] associated_R, having:

the asynchronous operation uses the associator trait to compute:

that meet the requirements defined in R. For convenience, these are also accessible via type alias associated_R_t<S, C> and free function get_associated_R(s, c), respectively.

The trait's primary template is specified such that: