C numeric limits interface

 

C++

Language

Standard library headers

Concepts

Utilities library

Strings library

Containers library

Algorithms library

Iterators library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Utilities library

Type support (basic types, RTTI, type traits)

Dynamic memory management

Error handling

Program utilities

Variadic functions

Date and time

Function objects

initializer_list (C++11)

bitset

hash (C++11)

Relational operators

rel_ops::operator!=rel_ops::operator>rel_ops::operator<=rel_ops::operator>=

optional, any and variant (C++17)

optional

any

variant

in_placein_place_typein_place_indexin_place_tin_place_type_tin_place_index_t

Pairs and tuples

pair

tuple (C++11)

apply (C++17)

make_from_tuple (C++17)

piecewise_construct_t (C++11)

piecewise_construct (C++11)

integer_sequence (C++14)

Swap, forward and move

swap

exchange (C++14)

forward (C++11)

move (C++11)

move_if_noexcept (C++11)

Elementary string conversions

to_chars (C++17)

from_chars (C++17)

chars_format (C++17)

Type operations

declval (C++11)

as_const (C++17)

 

Type support

Basic types
Fundamental types
Fixed width integer types (C++11)
ptrdiff_t size_t max_align_t (C++11) byte (C++17)	nullptr_t (C++11) offsetof NULL
Numeric limits
numeric_limits
C numeric limits interface
Runtime type information
type_info type_index (C++11)	bad_typeid bad_cast
Type traits
Type categories
is_void (C++11) is_null_pointer (C++14) is_array (C++11) is_pointer (C++11) is_enum (C++11) is_union (C++11) is_class (C++11) is_function (C++11)	is_object (C++11) is_scalar (C++11) is_compound (C++11) is_integral (C++11) is_floating_point (C++11) is_fundamental (C++11) is_arithmetic (C++11)
is_reference (C++11)
is_lvalue_reference (C++11)
is_rvalue_reference (C++11)
is_member_pointer (C++11)
is_member_object_pointer (C++11)
is_member_function_pointer (C++11)

Type properties
is_const (C++11) is_volatile (C++11) is_pod (C++11) is_empty (C++11) is_polymorphic (C++11) is_final (C++14) is_abstract (C++11)	is_trivial (C++11) is_trivially_copyable (C++11) is_standard_layout (C++11) is_literal_type (C++11)(deprecated in C++17) is_aggregate (C++17) is_signed (C++11) is_unsigned (C++11)
has_unique_object_representations (C++17)
Type trait constants
integral_constantbool_constanttrue_typefalse_type (C++11)(C++17)(C++11)(C++11)
Metafunctions
conjunction (C++17)
disjunction (C++17)
negation (C++17)

Supported operations
is_constructibleis_trivially_constructibleis_nothrow_constructible (C++11)(C++11)(C++11)
is_default_constructibleis_trivially_default_constructibleis_nothrow_default_constructible (C++11)(C++11)(C++11)
is_copy_constructibleis_trivially_copy_constructibleis_nothrow_copy_constructible (C++11)(C++11)(C++11)
is_move_constructibleis_trivially_move_constructibleis_nothrow_move_constructible (C++11)(C++11)(C++11)
is_assignableis_trivially_assignableis_nothrow_assignable (C++11)(C++11)(C++11)
is_copy_assignableis_trivially_copy_assignableis_nothrow_copy_assignable (C++11)(C++11)(C++11)
is_move_assignableis_trivially_move_assignableis_nothrow_move_assignable (C++11)(C++11)(C++11)
is_destructibleis_trivially_destructibleis_nothrow_destructible (C++11)(C++11)(C++11)
has_virtual_destructor (C++11)
is_swappable_withis_swappableis_nothrow_swappable_withis_nothrow_swappable (C++17)(C++17)(C++17)(C++17)
Relationships and property queries
is_same (C++11) is_base_of (C++11) is_convertible (C++11)	alignment_of (C++11) rank (C++11) extent (C++11)
is_invocableis_invocable_ris_nothrow_invocableis_nothrow_invocable_r (C++17)(C++17)(C++17)(C++17)
Type modifications
remove_cvremove_constremove_volatile (C++11)(C++11)(C++11) add_cvadd_constadd_volatile (C++11)(C++11)(C++11) make_signed (C++11) make_unsigned (C++11)	remove_reference (C++11) add_lvalue_referenceadd_rvalue_reference (C++11)(C++11) remove_pointer (C++11) add_pointer (C++11) remove_extent (C++11) remove_all_extents (C++11)
Type transformations
aligned_storage (C++11) aligned_union (C++11) decay (C++11) enable_if (C++11) void_t (C++17)	conditional (C++11) common_type (C++11) underlying_type (C++11) result_ofinvoke_result (C++11)(deprecated in C++17)(C++17)

 

See also std::numeric_limits interface.

Defined in header <cstdint>
PTRDIFF_MIN (C++11)	minimum value of object of std::ptrdiff_t type (macro constant)
PTRDIFF_MAX (C++11)	maximum value of object of std::ptrdiff_t type (macro constant)
SIZE_MAX (C++11)	maximum value of object of std::size_t type (macro constant)
SIG_ATOMIC_MIN (C++11)	minimum value of object of std::sig_atomic_t type (macro constant)
SIG_ATOMIC_MAX (C++11)	maximum value of object of std::sig_atomic_t type (macro constant)
WCHAR_MIN (C++11)	minimum value of object of wchar_t type (macro constant)
WCHAR_MAX (C++11)	maximum value of object of wchar_t type (macro constant)
WINT_MIN (C++11)	minimum value of object of std::wint_t type (macro constant)
WINT_MAX (C++11)	maximum value of object of std::wint_t type (macro constant)

Limits of integer types

Defined in header <climits>
CHAR_BIT	number of bits in byte (macro constant)
MB_LEN_MAX	maximum number of bytes in a multibyte character (macro constant)
CHAR_MIN	minimum value of char (macro constant)
CHAR_MAX	maximum value of char (macro constant)
SCHAR_MINSHRT_MININT_MINLONG_MINLLONG_MIN (C++11)	minimum value of signed char, short, int, long and long long respectively (macro constant)
SCHAR_MAXSHRT_MAXINT_MAXLONG_MAXLLONG_MAX (C++11)	maximum value of signed char, short, int, long and long long respectively (macro constant)
UCHAR_MAXUSHRT_MAXUINT_MAXULONG_MAXULLONG_MAX (C++11)	maximum value of unsigned char, unsigned short, unsigned int, unsigned long and unsigned long long respectively (macro constant)

Note: the types of these constants, other than CHAR_BIT and MB_LEN_MAX, are required to match the results of the integral promotions as applied to objects of the types they describe: CHAR_MAX may have type int or unsigned int, but never char. Similarly USHRT_MAX may not be of an unsigned type: its type may be int.

Limits of floating point types

Defined in header <cfloat>
FLT_RADIX	the radix (integer base) used by the representation of all three floating-point types (macro constant)
DECIMAL_DIG (C++11)	conversion from long double to decimal with at least DECIMAL_DIG digits and back to long double is the identity conversion. : this is the decimal precision required to serialize/deserialize a long double (see also std::numeric_limits::max_digits10) (macro constant)
FLT_DECIMAL_DIGDBL_DECIMAL_DIGLDBL_DECIMAL_DIG (C++17)	conversion from float/double/long double to decimal with at least FLT_DECIMAL_DIG/DBL_DECIMAL_DIG/LDBL_DECIMAL_DIG digits and back is the identity conversion. : this is the decimal precision required to serialize/deserialize a floating-point value (see also std::numeric_limits::max_digits10). Defined to at least 6, 10, and 10 respectively, or 9 for IEEE float and 17 for IEEE double. (macro constant)
FLT_MINDBL_MINLDBL_MIN	minimum normalized positive value of float, double and long double respectively (macro constant)
FLT_TRUE_MINDBL_TRUE_MINLDBL_TRUE_MIN (C++17)	minimum positive value of float, double and long double respectively (macro constant)
FLT_MAXDBL_MAXLDBL_MAX	maximum value of float, double and long double respectively (macro constant)
FLT_EPSILONDBL_EPSILONLDBL_EPSILON	difference between 1.0 and the next representable value for float, double and long double respectively (macro constant)
FLT_DIGDBL_DIGLDBL_DIG	number of decimal digits that are guaranteed to be preserved in text -> float/double/long double -> text roundtrip without change due to rounding or overflow (see std::numeric_limits::digits10 for explanation) (macro constant)
FLT_MANT_DIGDBL_MANT_DIGLDBL_MANT_DIG	number of base FLT_RADIX digits that can be represented without losing precision for float, double and long double respectively (macro constant)
FLT_MIN_EXPDBL_MIN_EXPLDBL_MIN_EXP	minimum negative integer such that FLT_RADIX raised by power one less than that integer is a normalized float, double and long double respectively (macro constant)
FLT_MIN_10_EXPDBL_MIN_10_EXPLDBL_MIN_10_EXP	minimum negative integer such that 10 raised by power one less than that integer is a normalized float, double and long double respectively (macro constant)
FLT_MAX_EXPDBL_MAX_EXPLDBL_MAX_EXP	maximum positive integer such that FLT_RADIX raised by power one more than that integer is a normalized float, double and long double respectively (macro constant)
FLT_MAX_10_EXPDBL_MAX_10_EXPLDBL_MAX_10_EXP	maximum positive integer such that 10 raised by power one more than that integer is a normalized float, double and long double respectively (macro constant)
FLT_ROUNDS	default rounding mode of floating-point arithmetics (macro constant)
FLT_EVAL_METHOD (C++11)	specifies in what precision all arithmetic operations are done (macro constant)
FLT_HAS_SUBNORMDBL_HAS_SUBNORMLDBL_HAS_SUBNORM (C++17)	specifies whether the type supports subnormal (denormal) numbers: -1 indeterminable, 0 absent, 1 present (macro constant)

See also

• Fixed width integer types
• Arithmetic types
• C++ type system overview
• Type support (basic types, RTTI, type traits)