Col.aggregate

Undocumented in source. Be warned that the author may not have intended to support it.
struct Col
aggregate
(
S = BO
K
)
(,
in BsonObject options = BsonObject.init
,
in QueryFlags flags = QueryFlags.NONE
,
in ReadPrefs readPrefs = null
)
if (
is(Unqual!K == BsonArray) ||
is(Unqual!K == BsonObject)
)

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