The flow control constructs described in Transitions and Loop Begin and Loop End require or support the evaluation of conditions to determine how the workflow should proceed. The Loop Begin activities must have some metadata that specifies the loop exit conditions, while transitions can optionally have a condition to decide whether or not the given transition will be followed.
This chapter describes the process definition metadata construct that represents a condition. A condition is a list of expressions that perform logical operations on workflow data objects attributes. The condition itself is a compound whose value is conjunction or disjunction of its constituent expressions. The parent constructs (loops and transitions) are responsible for taking appropriate actions as a result of the evaluation of conditions.