Files
Go-http_framework/vendor/github.com/ahmetb/go-linq/intersect.go
T

68 lines
1.6 KiB
Go

package linq
// Intersect produces the set intersection of the source collection and the
// provided input collection. The intersection of two sets A and B is defined as
// the set that contains all the elements of A that also appear in B,
// but no other elements.
func (q Query) Intersect(q2 Query) Query {
return Query{
Iterate: func() Iterator {
next := q.Iterate()
next2 := q2.Iterate()
set := make(map[interface{}]bool)
for item, ok := next2(); ok; item, ok = next2() {
set[item] = true
}
return func() (item interface{}, ok bool) {
for item, ok = next(); ok; item, ok = next() {
if _, has := set[item]; has {
delete(set, item)
return
}
}
return
}
},
}
}
// IntersectBy produces the set intersection of the source collection and the
// provided input collection. The intersection of two sets A and B is defined as
// the set that contains all the elements of A that also appear in B,
// but no other elements.
//
// IntersectBy invokes a transform function on each element of both collections.
func (q Query) IntersectBy(
q2 Query,
selector func(interface{}) interface{},
) Query {
return Query{
Iterate: func() Iterator {
next := q.Iterate()
next2 := q2.Iterate()
set := make(map[interface{}]bool)
for item, ok := next2(); ok; item, ok = next2() {
s := selector(item)
set[s] = true
}
return func() (item interface{}, ok bool) {
for item, ok = next(); ok; item, ok = next() {
s := selector(item)
if _, has := set[s]; has {
delete(set, s)
return
}
}
return
}
},
}
}