// until C++20 bool operator!=(const_reference lhs, const_reference rhs) noexcept; // (1) template<typename ScalarType> bool operator!=(const_reference lhs, const ScalarType rhs) noexcept; // (2) template<typename ScalarType> bool operator!=(ScalarType lhs, const const_reference rhs) noexcept; // (2) // since C++20 class basic_json { bool operator!=(const_reference rhs) const noexcept; // (1) template<typename ScalarType> bool operator!=(ScalarType rhs) const noexcept; // (2) };
Compares two JSON values for inequality according to the following rules:
#!cpp false
if (1) either operand is discarded, or (2) either operand is NaN
and the other operand is either NaN
or any other number.#!cpp !(lhs == rhs)
(until C++20) or #!cpp !(*this == rhs)
(since C++20).Compares a JSON value and a scalar or a scalar and a JSON value for inequality by converting the scalar to a JSON value and comparing both JSON values according to 1.
ScalarType
: a scalar type according to std::is_scalar<ScalarType>::value
lhs
(in) : first value to consider
rhs
(in) : second value to consider
whether the values lhs
/*this
and rhs
are not equal
No-throw guarantee: this function never throws exceptions.
Linear.
!!! note “Comparing NaN
”
`NaN` values are unordered within the domain of numbers. The following comparisons all yield `#!cpp false`: 1. Comparing a `NaN` with itself. 2. Comparing a `NaN` with another `NaN`. 3. Comparing a `NaN` and any other number.
??? example
The example demonstrates comparing several JSON types. ```cpp --8<-- "examples/operator__notequal.cpp" ``` Output: ```json --8<-- "examples/operator__notequal.output" ```
??? example
The example demonstrates comparing several JSON types against the null pointer (JSON `#!json null`). ```cpp --8<-- "examples/operator__notequal__nullptr_t.cpp" ``` Output: ```json --8<-- "examples/operator__notequal__nullptr_t.output" ```