deltas.Group(GroupName("^[^:]*"))

ledger/group.go

@@ -4,6 +4,15 @@ import "regexp"
 
 type Group func(Delta) Delta
 
+type Groups []Group
+
+func (groups Groups) Each(d Delta) Delta {
+	for i := range groups {
+		d = groups[i](d)
+	}
+	return d
+}
+
 func GroupDate(pattern string) Group {
 	p := regexp.MustCompile(pattern)
 	return func(d Delta) Delta {