lesson 10 extend

Author: dmitriz

examples/10-fold-map.js

@@ -1,3 +1,5 @@
+// folding a type
+
 const { Map, List } = require('immutable-ext')
 const { Sum } = require('../examples/monoid')
 
@@ -11,14 +13,16 @@ const res = List.of(Sum(1), Sum(33), Sum(4))
 console.log(res)
 
 
-const r1 = Map({
-  brian: 3,
-  sara: 5
-})
-.map(Sum)
-.fold(Sum.empty())
+const r1 = Map({ brian: 3, sara: 5 })
+  .map(Sum)
+  .fold(Sum.empty())
+
+const r11 = Map({ brian: 3, sara: 5 })
+
+  // run function Sum on each value, then fold
+  .foldMap(Sum, Sum.empty())
 
-console.log(r1)
+console.log(r1, r11)
 
 
 const r2 = List.of(1,3,45)