# nlohmann::basic_json::is_number_integer ```cpp constexpr bool is_number_integer() const noexcept; ``` This function returns `#!cpp true` if and only if the JSON value is a signed or unsigned integer number. This excludes floating-point values. ## Return value `#!cpp true` if type is an integer or unsigned integer number, `#!cpp false` otherwise. ## Exception safety No-throw guarantee: this member function never throws exceptions. ## Complexity Constant. ## Examples ??? example The following code exemplifies `is_number_integer()` for all JSON types. ```cpp --8<-- "examples/is_number_integer.cpp" ``` Output: ```json --8<-- "examples/is_number_integer.output" ``` ## See also - [is_number()](is_number.md) check if value is a number - [is_number_unsigned()](is_number_unsigned.md) check if value is an unsigned integer number - [is_number_float()](is_number_float.md) check if value is a floating-point number ## Version history - Added in version 1.0.0. - Extended to also return `#!cpp true` for unsigned integers in 2.0.0.