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