Leg
Key Leg in Multi Leg Swap refers to the 1D-array of swap legs, whereby each of them represents a certain stream of cash flows that share a common denomination currency, which currency may differ among the legs.
While the collection of all cash flows is unique for any given Multi Leg Swap product, its segregation into legs is arbitrary.
Each array element, i.e. each leg, is represented by an object of type Bond or BondExt