[concept.same] # 18 Concepts library [[concepts]](./#concepts) ## 18.4 Language-related concepts [[concepts.lang]](concepts.lang#concept.same) ### 18.4.2 Concept same_as [concept.same] [🔗](#itemdecl:1) `template concept [same-as-impl](#concept:same-as-impl "18.4.2 Concept same_­as [concept.same]") = [is_same_v](meta.type.synop#lib:is_same_v "21.3.3 Header synopsis [meta.type.synop]"); // exposition only template concept [same_as](#concept:same_as "18.4.2 Concept same_­as [concept.same]") = [same-as-impl](#concept:same-as-impl "18.4.2 Concept same_­as [concept.same]") && [same-as-impl](#concept:same-as-impl "18.4.2 Concept same_­as [concept.same]"); ` [1](#1) [#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/concepts.tex#L309) [*Note [1](#note-1)*: [same_as](#concept:same_as "18.4.2 Concept same_­as [concept.same]") subsumes [same_as](#concept:same_as "18.4.2 Concept same_­as [concept.same]") and vice versa[.](#1.sentence-1) — *end note*]