status-go/vendor/github.com/ipfs/go-cid/set.go

66 lines
1.2 KiB
Go

package cid
// Set is a implementation of a set of Cids, that is, a structure
// to which holds a single copy of every Cids that is added to it.
type Set struct {
set map[Cid]struct{}
}
// NewSet initializes and returns a new Set.
func NewSet() *Set {
return &Set{set: make(map[Cid]struct{})}
}
// Add puts a Cid in the Set.
func (s *Set) Add(c Cid) {
s.set[c] = struct{}{}
}
// Has returns if the Set contains a given Cid.
func (s *Set) Has(c Cid) bool {
_, ok := s.set[c]
return ok
}
// Remove deletes a Cid from the Set.
func (s *Set) Remove(c Cid) {
delete(s.set, c)
}
// Len returns how many elements the Set has.
func (s *Set) Len() int {
return len(s.set)
}
// Keys returns the Cids in the set.
func (s *Set) Keys() []Cid {
out := make([]Cid, 0, len(s.set))
for k := range s.set {
out = append(out, k)
}
return out
}
// Visit adds a Cid to the set only if it is
// not in it already.
func (s *Set) Visit(c Cid) bool {
if !s.Has(c) {
s.Add(c)
return true
}
return false
}
// ForEach allows to run a custom function on each
// Cid in the set.
func (s *Set) ForEach(f func(c Cid) error) error {
for c := range s.set {
err := f(c)
if err != nil {
return err
}
}
return nil
}