static const bool has_signaling_NaN; | (until C++11) | |

static constexpr bool has_signaling_NaN; | (since C++11) |

The value of `std::numeric_limits<T>::has_signaling_NaN`

is `true`

for all types `T`

capable of representing the special value "Signaling Not-A-Number". This constant is meaningful for all floating-point types and is guaranteed to be `true`

if `std::numeric_limits<T>::is_iec559 == true`

.

`T` | value of `std::numeric_limits<T>::has_signaling_NaN` |
---|---|

/* non-specialized */ | `false` |

`bool` | `false` |

`char` | `false` |

`signed char` | `false` |

`unsigned char` | `false` |

`wchar_t` | `false` |

`char16_t` | `false` |

`char32_t` | `false` |

`short` | `false` |

`unsigned short` | `false` |

`int` | `false` |

`unsigned int` | `false` |

`long` | `false` |

`unsigned long` | `false` |

`long long` | `false` |

`unsigned long long` | `false` |

`float` | usually `true` |

`double` | usually `true` |

`long double` | usually `true` |

[static] | returns a quiet NaN value of the given floating-point type (public static member function) |

[static] | identifies floating-point types that can represent the special value "positive infinity" (public static member constant) |

[static] | identifies floating-point types that can represent the special value "quiet not-a-number" (NaN) (public static member constant) |

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