static const int digits; | (until C++11) | |

static constexpr int digits; | (since C++11) |

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

is the number of digits in base-radix that can be represented by the type `T`

without change. For integer types, this is the number of bits not counting the sign bit and the padding bits (if any). For floating-point types, this is the digits of the mantissa (for IEC 559/IEEE 754 implementations, this is the number of digits stored for the mantissa plus one, because the mantissa has an implicit leading 1 and binary point).

`T` | value of `std::numeric_limits<T>::digits` (assuming no padding bits) |
---|---|

/* non-specialized */ | `0` |

bool | `1` |

char | `CHAR_BIT - std::numeric_limits<char>::is_signed` |

signed char | `CHAR_BIT - 1` |

unsigned char | `CHAR_BIT` |

wchar_t | `CHAR_BIT * sizeof(wchar_t)` |

char8_t (since C++20) | `CHAR_BIT` |

char16_t (since C++11) | `CHAR_BIT * sizeof(char16_t)` |

char32_t (since C++11) | `CHAR_BIT * sizeof(char32_t)` |

short | `CHAR_BIT * sizeof(short) - 1` |

unsigned short | `CHAR_BIT * sizeof(short)` |

int | `CHAR_BIT * sizeof(int) - 1` |

unsigned int | `CHAR_BIT * sizeof(int)` |

long | `CHAR_BIT * sizeof(long) - 1` |

unsigned long | `CHAR_BIT * sizeof(long)` |

long long (since C++11) | `CHAR_BIT * sizeof(long long) - 1` |

unsigned long long (since C++11) | `CHAR_BIT * sizeof(long long)` |

float | `FLT_MANT_DIG` |

double | `DBL_MANT_DIG` |

long double | `LDBL_MANT_DIG` |

[static] | the radix or integer base used by the representation of the given type (public static member constant) |

[static] | one more than the smallest negative power of the radix that is a valid normalized floating-point value (public static member constant) |

[static] | one more than the largest integer power of the radix that is a valid finite floating-point value (public static member constant) |

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