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74 lines
1.5 KiB
Markdown
74 lines
1.5 KiB
Markdown
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# basic_json::operator<
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```cpp
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bool operator<(const_reference lhs, const_reference rhs) noexcept,
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template<typename ScalarType>
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bool operator<(const_reference lhs, const ScalarType rhs) noexcept;
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template<typename ScalarType>
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bool operator<(ScalarType lhs, const const_reference rhs) noexcept;
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```
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Compares whether one JSON value `lhs` is less than another JSON value `rhs` according to the following rules:
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- If `lhs` and `rhs` have the same type, the values are compared using the default `<` operator.
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- Integer and floating-point numbers are automatically converted before comparison
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- Discarded values a
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- In case `lhs` and `rhs` have different types, the values are ignored and the order of the types is considered, which
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is:
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1. null
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2. boolean
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3. number (all types)
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4. object
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5. array
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6. string
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7. binary
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For instance, any boolean value is considered less than any string.
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## Template parameters
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`ScalarType`
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: a scalar type according to `std::is_scalar<ScalarType>::value`
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## Parameters
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`lhs` (in)
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: first value to consider
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`rhs` (in)
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: second value to consider
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## Return value
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whether `lhs` is less than `rhs`
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## Exception safety
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No-throw guarantee: this function never throws exceptions.
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## Complexity
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Linear.
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## Example
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??? example
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The example demonstrates comparing several JSON types.
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```cpp
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--8<-- "examples/operator__less.cpp"
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```
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Output:
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```json
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--8<-- "examples/operator__less.output"
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```
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## Version history
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- Added in version 1.0.0.
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