Querying null objects

Including queries in macros : Understanding the available query criteria : Querying null objects

Querying null objects

Null objects support all common query criteria (see Understanding the available query criteria).

You can call any method on a null object; the call will succeed, and value null will be returned. Thus, null.somemethod() returns null.

Using query operators with null objects

False is returned when a null object is used with the following comparison operators: =, ==, <, >, >=, and <=. For example, null = 5 returns False. However, please note the following exceptions:

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When two null objects are compared by using the equality operator = or ==, True is returned.

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When a null object is compared to a non-null object by using the inequality operator <>, True is returned.


Example	Result
`null = 3`	False
`null = 'test'`	False
`null = null`	True
`null <> 3`	True
`null <> null`	False
`3 > null`	False
`null > null`	False
`null >= null`	False