---
name: "std::relation"
section: "3cxx"
platform: "linux"
package: "libstdc++-12-doc"
version: "12.4.0-5"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/std::relation/3cxx"
---

# std::relation(3cxx)

\[concept.relation\], concept relation

## NAME

std::relation - \[concept.relation\], concept relation

## SYNOPSIS

`#include <concepts>`

## Concept definition

```
template<typename _Rel, typename _Tp, typename _Up>
concept std::relation =  predicate<_Rel, _Tp, _Tp> && predicate<_Rel, _Up, _Up>
      && predicate<_Rel, _Tp, _Up> && predicate<_Rel, _Up, _Tp>
```

## Detailed Description

\[concept.relation\], concept relation

## Author

Generated automatically by Doxygen for libstdc++ from the source code.