INCLUDES

INCLUDES(set, task)

TRUE if a given row is in a set, such as whether a task lies upstream of the substantial-completion milestone. The second argument is a row, like TASK("MS_SUB") or [Task], never a task code as text.

Arguments

ArgumentWhat to give it
setA set of tasks, WBS nodes, resources or assignments: Upstream, All, ROWS(…). Sets of links (InLinks, OutLinks) aren't accepted.
taskOne row of the same kind: TASK("BDC_001"), [Task], FIRST(…). When it is blank, the result is blank.

Examples

Formula
=INCLUDES(Downstream, TASK("MS_SUB"))

TRUE for every task that leads, directly or not, to the substantial-completion milestone.

Formula
=INCLUDES(DrivingDownstream, TASK("FINISH"))

TRUE for tasks on the chain that drives the project finish.

Formula
=INCLUDES(ROWS(Relationships[Predecessor]), [Task])

TRUE when the task is the predecessor of at least one relationship, so it leads somewhere.

Reach for something else when

You wantUse
Whether a set has any rowsISEMPTY
How many of a set's rows are also in another setCOUNT(INTERSECT(…))
Whether any row of a set meets a conditionANY

Common questions

Why does the editor say "INCLUDES can't use Text here"?

A task code in quotes is text, not a task. Wrap it in TASK:

The editor refuses this
=INCLUDES(Upstream, "BDC_001")

INCLUDES(Upstream, TASK("BDC_001")) is the working form.