+
+ # Does `self` and `other` have the same keys associated with the same values?
+ #
+ # ~~~
+ # var a = new HashMap[String, Int]
+ # var b = new ArrayMap[Object, Numeric]
+ # assert a == b
+ # a["one"] = 1
+ # assert a != b
+ # b["one"] = 1
+ # assert a == b
+ # b["one"] = 2
+ # assert a != b
+ # ~~~
+ redef fun ==(other)
+ do
+ if not other isa MapRead[nullable Object, nullable Object] then return false
+ if other.length != self.length then return false
+ for k, v in self do
+ if not other.has_key(k) then return false
+ if other[k] != v then return false
+ end
+ return true
+ end
+
+ # A hashcode based on the hashcode of the keys and the values.
+ #
+ # ~~~
+ # var a = new HashMap[String, Int]
+ # var b = new ArrayMap[Object, Numeric]
+ # a["one"] = 1
+ # b["one"] = 1
+ # assert a.hash == b.hash
+ # ~~~
+ redef fun hash
+ do
+ var res = length
+ for k, v in self do
+ if k != null then res += k.hash * 7
+ if v != null then res += v.hash * 11
+ end
+ return res
+ end