What's the difference between clear and arrayValue in jsoncpp

Question

To work with json using a library jsoncpp. Previously created an array of objects can be cleared by clear.

Json::Value value;
...
value.clear();

Also, it can be purified by arrayValue (or nullValue).

Json::Value value;
...
value = Json::arrayValue;

Question: What's the difference between clear and arrayValue?

Answer 1

null, empty array, and empty object are three different things in JsonCpp.

value.clear() does the following:

• null -> null
• any array -> empty array
• any object -> empty object
• anything else -> throw std::runtime_error

value = Json:arrayValue does the following:

• anything -> empty array

So the two constructs are not semantically equivalent.