Create compact-object.ts

Author: kamyu104

TypeScript/compact-object.ts

@@ -0,0 +1,25 @@
+// Time:  O(n)
+// Space: O(h)
+
+type Obj = Record<any, any>;
+
+// dfs
+function compactObject(obj: Obj): Obj {
+    if (obj === null) {
+        return null;
+    }
+    if (Array.isArray(obj)) {
+        return obj.filter(Boolean).map(compactObject);
+    }
+    if (typeof obj !== "object") {
+        return obj;
+    }
+    return Object.keys(obj).reduce(
+        (accu, key) => {
+            accu[key] = compactObject(obj[key]);
+            if (!Boolean(accu[key])) {
+                delete accu[key];
+            }
+            return accu;
+        }, {});
+};