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from ecflow import Defs,Suite,Task,Trigger,Complete

defs = Defs( 
        Suite("s1",
           Task("t1"),
           Task("t2"),
           Task("t3",
               Trigger("t1 == complete"),   
               Trigger("t2 == active"),           # added as a AND
               Trigger("t2 == aborted",False))))  # False mean add with OR
t3 TRIGGER
(t1 == complete and t2 == active or t2 == active) 

The following show alternative styles that produce the same definition:

defs = Defs()
s1 = defs.add_suite("s1") 
t1 = s1.add_task("t1")
t2 = s1.add_task("t2")
t3 = s1.add_task("t3")
t3.add_part_trigger( "t1 == complete")
t3.add_part_trigger( "t2 == active", True) 
# here True means add as 'AND'
t3.add_part_trigger( "t2 == aborted", False) 
# here False means add as 'OR'
defs = Defs().add(
         Suite("s1").add(
           Task("t1"),
           Task("t2"),
           Task("t3").add(
             Trigger("t1 == complete"), 
             Trigger("t2 == active"),
             Trigger("t2 == aborted",False))))
defs = Defs() + Suite("s1")
defs.s1 += [ Task("t{}".format(i)) for i in range(1,4) ]
defs.s1.t3 += [ Trigger("t1 == complete"),
                Trigger("t2 == active"),
                Trigger("t2 == aborted",False) ]


In the example above we use 'defs.s1.t3' to reference a node by name. This is useful in small designs but will produce maintenance issues in large designs IF the node names are changed.