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Version: 8.3

Unary-tests

A unary-tests expression is a special kind of boolean expression. Unary-tests expressions should be used for the input entries of a decision table (i.e. the conditions of a rule).

A unary-tests expression returns true if one of the following conditions is fulfilled:

  • The expression evaluates to true when the input value is applied to the unary operators.
  • The expression evaluates to true when the input value is assigned to the special variable ?.
  • The expression evaluates to a value, and the input value is equal to that value.
  • The expression evaluates to a list, and the input value is equal to at least one of the values.
  • The expression is equal to - (a dash).

Comparison

Compares the input value with a given value. The input value is passed implicitly as the first argument of the operator.

Both values must be of the same type. Otherwise, the result is null.

OperatorDescriptionSupported types
(none)equal toany
<less thannumber, date, time, date-time, duration
<=less than or equal tonumber, date, time, date-time, duration
>greater thannumber, date, time, date-time, duration
>=greater than or equalnumber, date, time, date-time, duration
"valid"

< 10

<= date("2020-04-06")

> time("08:00:00")

>= duration("P5D")

Interval

Checks if the input value is within a given interval between x and y.

An interval has two boundaries that can be open (x..y) / ]x..y[ or closed [x..y]. If a boundary is closed, it includes the given value (i.e. less/greater than or equal). Otherwise, it excludes the value (i.e. less/greater than).

The input value is passed implicitly to the operator.

(2..5)
// input > 2 and input < 5

]2..5[
// input > 2 and input < 5

[2..5]
// input >= 2 and input <= 5

(2..5]
// input > 2 and input <= 5

Disjunction/or

Combines multiple unary-test expressions following the ternary logic.

  • Returns true if at least one unary-test evaluates to true.
  • Otherwise, it returns false.
2, 3, 4
// input = 2 or input = 3 or input = 4

< 10, > 50
// input < 10 or input > 50

Negation/not

Negates a given unary-test expression. The expression can be a comparison, an interval, or a disjunction.

It returns true if the given unary-test evaluates to false.

not("valid")
// input != "valid"

not(2, 3)
// input != 2 and input != 3

Expressions

When a unary operator is not enough to express the condition, any expression that returns a boolean value can be used, such as invoking a function.

In the expression, the input value can be accessed by the special variable ?.

contains(?, "good")
// checks if the input value (string) contains "good"

ends with(?, "@camunda.com")
// checks if the input value (string) ends with "@camunda.com"