The slice_map is designed to impove the performance for the case that you need to hold a large map in memory. It uses a slice and an extra index map to replace the go-standard map such as map[int]interface for better add/iter performance.

If you have a large map (more than 500k keys and use complex struct as map value), slice_map saves lots of cpu time when every GC excuting.

Adding/deleting elements:

type OBJ struct {
	// ...
    int id
}

// Need to implement a Id interface.
func (o *Obj) LMapId() int {
	return o.id
}

lm := NewLMap()
newObj := OBJ{ id: 1024 }
lm.Add()
lm.Del(newObj.id)
lm.Len()

Iter the slice_map: When use FastIter, you can't delete keys in the map. And get 10 times faster than Iter which you can delete keys safely during the iterting.

lm.FastIter(func(tmp LMapObj) {
	obj, ok := tmp.(*OBJ)
	...
})

lm.Iter(func(tmp LMapObj) {
	obj, ok := tmp.(*OBJ)
	...
})