finished ch15.4

.obsidian/workspace.json

@@ -27,30 +27,40 @@
             "state": {
               "type": "markdown",
               "state": {
-                "file": "Tests.md",
+                "file": "Smart Pointers.md",
                 "mode": "source",
                 "source": false
               },
               "icon": "lucide-file",
-              "title": "Tests"
+              "title": "Smart Pointers"
             }
           },
           {
-            "id": "ec34d2df2728a299",
+            "id": "7615e7dc6a30893a",
             "type": "leaf",
             "state": {
               "type": "markdown",
               "state": {
-                "file": "minigrep/README.md",
+                "file": "Reference Counter Smart Pointer.md",
                 "mode": "source",
                 "source": false
               },
               "icon": "lucide-file",
-              "title": "README"
+              "title": "Reference Counter Smart Pointer"
+            }
+          },
+          {
+            "id": "6ed9f182aa3d5f3e",
+            "type": "leaf",
+            "state": {
+              "type": "graph",
+              "state": {},
+              "icon": "lucide-git-fork",
+              "title": "Graph view"
             }
           }
         ],
-        "currentTab": 2
+        "currentTab": 3
       }
     ],
     "direction": "vertical"
@@ -193,11 +203,18 @@
       "command-palette:Open command palette": false
     }
   },
-  "active": "ec34d2df2728a299",
+  "active": "6ed9f182aa3d5f3e",
   "lastOpenFiles": [
-    "Writing_Tests.md",
+    "Reference Counter Smart Pointer.md",
+    "Smart Pointers.md",
+    "Ref Cell Mutability.md",
+    "The Performance Closures and Iterators.md",
+    "Improving The IO Project.md",
     "Tests.md",
+    "The Preformance Closures and Iterators.md",
     "minigrep/README.md",
+    "Project Organization.md",
+    "Writing_Tests.md",
     "minigrep/src/lib.rs",
     "Test_Organization.md",
     "Test Controls.md",
@@ -215,13 +232,6 @@
     "Data Types.md",
     "Enums.md",
     "Error Handling.md",
-    "Hash.md",
-    "ownership.md",
-    "Packages.md",
-    "Paths.md",
-    "Primitives.md",
-    "Project Organization.md",
-    "README.md",
     "does_not_compile.svg",
     "Untitled.canvas",
     "Good and Bad Code/Commenting Pratices",