[res.contract.assertions]

# 16 Library introduction [[library]](./#library)

## 16.4 Library-wide requirements [[requirements]](requirements#res.contract.assertions)

### 16.4.6 Conforming implementations [[conforming]](conforming#res.contract.assertions)

#### 16.4.6.15 Contract assertions [res.contract.assertions]

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/lib-intro.tex#L3960)

Unless specified otherwise,
an implementation may check
the specified preconditions and postconditions of a function
in the C++ standard library using contract
assertions ([[basic.contract]](basic.contract "6.11 Contract assertions"), [[structure.specifications]](structure.specifications "16.3.2.4 Detailed specifications"))[.](#1.sentence-1)
