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--- cplusplus:pointers_4_slides [2019/03/31 22:31] – mithat
+++ cplusplus:pointers_4_slides [2021/10/24 02:56] – [Memory management of dynamically allocated storage] mithat
@@ Line 11: / Line 11: @@
 ===== Dynamic memory allocation =====
   * **Dynamic memory allocation** allows you to reserve blocks of computer memory at //runtime//.
-  * Typically used without associating a variable name with it.
+  * Typically used with pointers.
 ===== The new operator =====
-  * ''new <data-type>'' reserves a block of memory to hold the specified %%<data-type>%% and returns the base address of that block:
+  * ''new <data-type>''
+    * reserves a block of memory to hold the specified %%<data-type>%%
+    * returns the base address of that block.
+    * optional parenthesis around ''<data-type>''
 <code cpp>
@@ Line 23: / Line 26: @@
 </code>
-  * ''foo'' points to a ''double'' that is //not// a variable.
+  * ''foo'' points to a ''double'' that isn't associated with a variable identifier.
 ===== Example =====
@@ Line 106: / Line 109: @@
 void ninetynine()
 {
-    int localVar = 99;
+    int localVar = 99;  // localVar is destroyed at end of fcn call
     cout << localVar << endl;
 }
@@ Line 136: / Line 139: @@
 void ninetynine()
 {
-    int *localPtr = new int;
+    int *localPtr = nullptr;  // localPtr is destroyed at end of fcn call
+    localPtr = new int;       // but not dynamically allocated storage
     *localPtr = 99;