metrics: make Counter a genuine Map

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/src/counter.nit b/src/counter.nit
index e7a7a9d..14b418d 100644 (file)
--- a/src/counter.nit
+++ b/src/counter.nit
@@ -15,30 +15,43 @@
 # Simple numerical statistical analysis and presentation
 module counter
 
-# A counter counts occurence of things
+# A counter counts occurrences of things
 # Use this instead of a HashMap[E, Int]
 class Counter[E: Object]
-       # Total number of counted occurences
+       super Map[E, Int]
+
+       # Total number of counted occurrences
        var total: Int = 0
 
        private var map = new HashMap[E, Int]
 
-       # The number of counted occurences of `e'
-       fun [](e: E): Int
+       # The number of counted occurrences of `e'
+       redef fun [](e: E): Int
        do
                var map = self.map
                if map.has_key(e) then return map[e]
                return 0
        end
 
-       # Count one more occurence of `e'
+       redef fun []=(e: E, value: Int)
+       do
+               total -= self[e]
+               self.map[e] = value
+               total += value
+       end
+
+       redef fun keys do return map.keys
+
+       redef fun values do return map.values
+
+       # Count one more occurrence of `e'
        fun inc(e: E)
        do
                self.map[e] = self[e] + 1
                total += 1
        end
 
-       # Return an array of elements sorted by occurences
+       # Return an array of elements sorted by occurrences
        fun sort: Array[E]
        do
                var res = map.keys.to_a