Unique type identifying a selected trait metafunction.
Synopsis
Declared in <bslmf_selecttrait.h>
template<template<class> typename t_TRAIT = SelectTrait_False>
struct SelectTraitCase;Description
This template expresses a class that is unique for the specified (template parameter) t_TRAIT metafunction. An instantiation of this template is the "compile‐time return value" of SelectTrait (see below). SelectTraitCase acts as a sort of compile‐time pointer‐to‐metafunction that holds the identity of a metafunction similar to the way a pointer‐to‐function holds (at run‐time) the identity of a function. As in the pointer‐to‐function case, a SelectTraitCase can also be used indirectly to evaluate t_TRAIT (at compile time). Also note that, when SelectTraitCase is specialized with the default t_TRAIT type parameter, SelectTrait_False, it essentially means that none of the traits specified to SelectTrait match.
Types
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