Merge pull request #188 from dentrado/add-getIn

Add getIn function

README.md

@@ -308,6 +308,18 @@ Immutable.setIn(obj, ["type", "sub"], "Norwegian Ridgeback");
 
 A second argument can be provided to perform a deep compare: `{deep: true}`.
 
+### getIn
+
+Returns the value at the given path. A default value can be provided as a second argument.
+
+```javascript
+var obj = Immutable({type: {main: "parrot", subtype: "Norwegian Blue"}, status: "alive"});
+Immutable.getIn(obj, ["type", "subtype"]);
+// returns "Norwegian Blue"
+Immutable.getIn(obj, ["type", "class"], "Aves");
+// returns "Aves"
+```
+
 ### update
 
 Returns an Immutable Object with a single property updated using the provided updater function.

seamless-immutable.development.js

@@ -203,6 +203,7 @@ function immutableInit(config) {
       addPropertyTo(array, "setIn", arraySetIn);
       addPropertyTo(array, "update", update);
       addPropertyTo(array, "updateIn", updateIn);
+      addPropertyTo(array, "getIn", getIn);
     }
 
     for(var i = 0, length = array.length; i < length; i++) {
@@ -551,6 +552,11 @@ function immutableInit(config) {
     return Immutable.setIn(this, path, updater.apply(initialVal, [initialVal].concat(restArgs)));
   }
 
+  function getIn(path, defaultValue) {
+    var value = getInPath(this, path);
+    return value === undefined ? defaultValue : value;
+  }
+
   function asMutableObject(opts) {
     var result = instantiateEmptyObject(this), key;
 
@@ -587,6 +593,7 @@ function immutableInit(config) {
       addPropertyTo(obj, "setIn", objectSetIn);
       addPropertyTo(obj, "update", update);
       addPropertyTo(obj, "updateIn", updateIn);
+      addPropertyTo(obj, "getIn", getIn);
     }
 
     return makeImmutable(obj, mutatingObjectMethods);
@@ -702,6 +709,7 @@ function immutableInit(config) {
   Immutable.setIn          = toStaticObjectOrArray(objectSetIn, arraySetIn);
   Immutable.update         = toStatic(update);
   Immutable.updateIn       = toStatic(updateIn);
+  Immutable.getIn          = toStatic(getIn);
   Immutable.flatMap        = toStatic(flatMap);
   Immutable.asObject       = toStatic(asObject);
   if (!globalConfig.use_static) {