Rewrite the tree using the new iteration object WIP

hyphae/iteration.go

@@ -0,0 +1,52 @@
+package hyphae
+
+import (
+	"sync"
+)
+
+// Iteration represents an iteration over all hyphae in the storage. You may use it instead of directly iterating using hyphae.YieldExistingHyphae when you want to do n checks at once instead of iterating n times.
+type Iteration struct {
+	sync.Mutex
+	iterator func() chan *Hypha
+	checks   []func(h *Hypha) CheckResult
+}
+
+func NewIteration() *Iteration {
+	return &Iteration{
+		iterator: YieldExistingHyphae,
+		checks:   make([]func(h *Hypha) CheckResult, 0),
+	}
+}
+
+// AddCheck adds the check to the iteration. It is concurrent-safe.
+func (i7n *Iteration) AddCheck(check func(h *Hypha) CheckResult) {
+	i7n.Lock()
+	i7n.checks = append(i7n.checks, check)
+	i7n.Unlock()
+}
+
+func (i7n *Iteration) removeCheck(i int) {
+	i7n.checks[i] = i7n.checks[len(i7n.checks)-1]
+	i7n.checks = i7n.checks[:len(i7n.checks)-1]
+}
+
+// Ignite does the iteration by walking over all hyphae yielded by the iterator used and calling all checks on the hypha. Ignited iterations are not concurrent-safe.
+func (i7n *Iteration) Ignite() {
+	for h := range i7n.iterator() {
+		for i, check := range i7n.checks {
+			if res := check(h); res == CheckForgetMe {
+				i7n.removeCheck(i)
+			}
+		}
+	}
+}
+
+// CheckResult is a result of an iteration check.
+type CheckResult int
+
+const (
+	// CheckContinue is returned when the check wants to be used next time too.
+	CheckContinue CheckResult = iota
+	// CheckForgetMe is returned when the check wants to be forgotten and not used anymore.
+	CheckForgetMe
+)