there is at least one (type)
This construct tests whether there is at least one object of a given type in a
collection.
Purpose
You use this construct to determine whether the specified collection contains at least one occurrence of a particular object.
Syntax
there is at least one <type> [in <list>] [where <test>,]
Description
Use the in clause to apply the test to a specific
collection of objects. Use one or more optional where
clauses to filter the objects to be counted with one or more conditions.
This construct can only be used in the if part of a
rule.
Example
The following condition tests whether or not a Customer object exists.
if
there is at least one customer
where...
then...
The following condition tests if a senior Gold customer exists.
definitions
set 'gold customers' to all customers in the customers of bank
where the category of each customer is Gold;
if
there is at least one customer in 'gold customers'
where the age of this customer is at least 60,
then...