public static BusinessRepoII <R> Apply <T, R>(
this BusinessRepoII <Func <T, R> > fthis,
BusinessRepoII <T> BT)
=> (from ft in fthis.Data
from t in BT.Data
select ft.Apply(t))
.ToBusinessRepoII();
public static BusinessRepoII <Func <T2, T3, T4, R> > Apply <T1, T2, T3, T4, R>(this BusinessRepoII <Func <T1, T2, T3, T4, R> > fthis, BusinessRepoII <T1> BT1)
=> (from ft in fthis.Data
from t in BT1.Data
select(ft.Apply(t)))
.ToBusinessRepoII();