json/doc/mkdocs/docs/api/basic_json/operator_lt.md

basic_json::operator<

bool operator<(const_reference lhs, const_reference rhs) noexcept,

template<typename ScalarType>
bool operator<(const_reference lhs, const ScalarType rhs) noexcept;

template<typename ScalarType>
bool operator<(ScalarType lhs, const const_reference rhs) noexcept;

Compares whether one JSON value lhs is less than another JSON value rhs according to the following rules:

• If lhs and rhs have the same type, the values are compared using the default < operator.

• Integer and floating-point numbers are automatically converted before comparison

• Discarded values a

• In case lhs and rhs have different types, the values are ignored and the order of the types is considered, which is:

  1. null
  2. boolean
  3. number (all types)
  4. object
  5. array
  6. string
  7. binary

  For instance, any boolean value is considered less than any string.

Template parameters

ScalarType

a scalar type according to std::is_scalar<ScalarType>::value

Parameters

lhs (in)

first value to consider

rhs (in)

second value to consider

Return value

whether lhs is less than rhs

Exception safety

No-throw guarantee: this function never throws exceptions.

Complexity

Linear.

Example

??? example

The example demonstrates comparing several JSON types.
    
```cpp
--8<-- "examples/operator__less.cpp"
```

Output:

```json
--8<-- "examples/operator__less.output"
```

Version history

• Added in version 1.0.0.