And Operator

And operator. Returns true if both parameters return true.

What	Type
Syntax	And(x, y)
x	bool
y	bool
Return type	bool

The And operator first evaluates the first parameter. Only if the first parameter evaluates to true, the second parameter is evaluated.

Example: And(Contains($title, "Lord"), Contains($author, "Tolkien"))

The fact that the evaluation is done parameter by parameter also opens up to using the following kinds of expressions (which are especially useful in filter definitions):

<SourceFilter>And(HasKey("MyLookup", $ID), MyLookup($ID, $Value) = "yes")</SourceFilter>

In this example, the first And argument checks that the field ID is actually in the lookup map. If it is, evaluating the second argument is safe.