Differences

This shows you the differences between two versions of the page.

--- cplusplus:pointers_2_slides [2021/10/19 19:33] – [Pointers as function parameters] mithat
+++ cplusplus:pointers_2_slides [2021/10/19 19:46] (current) – [Constant pointer to constant data] mithat
@@ Line 28: / Line 28: @@
   * Arguments can be anything that can be assigned to a pointer (i.e., addresses or pointers).
-===== Pointers as function parameters =====
+===== Example =====
 <file cpp function-with-pointer.cpp>
 /** Demonstrates how to pass pointers to functions. */
@@ Line 63: / Line 63: @@
   * Pointers can be used to implement //pass by reference// in functions.
   * The ''*'' operator is used to alias a variable inside of function.
-  * In the function below, ''*number'' is used as an alias for the variable passed in.
+  * Strictly speaking, the passing mechanism is //call by value//. But functionality is pass by reference.
-  * Strictly speaking, the passing mechanism is //call by value//. But functionally it's pass by reference.
+  * Syntax in function invocation (e.g., ''cubeByReference(&number))'' makes clear that a pointer is involved --- good indication that call by reference is used in the function.
-  * The syntax in the function invocation (e.g., ''cubeByReference(&number))'' makes it clear that a pointer is involved --- which is good indication that call by reference is being used.
+===== Example =====
 <file cpp cube-by-reference.cpp>
 /** Cube a variable using pass by reference with a pointer. */
@@ Line 85: / Line 85: @@
 void cubeByReference(int *nPtr)
 {
+    // *nptr'' is an alias for the variable passed in.
     *nPtr = (*nPtr) * (*nPtr) * (*nPtr); // parenthesis for readability
 }
@@ Line 103: / Line 104: @@
   * A **constant pointer** is a pointer whose value cannot change.
-  * Constant pointers store a memory location that cannot be changed.
+  * Constant pointers //store a memory location that cannot be changed//.
   * Must be initialized when declared.
-  * Use the ''const'' keyword between the ''*'' and the name of the pointer:
+  * ''const'' keyword goes between the ''*'' and the name of the pointer:
 <code c++>
 int *const myPtr = &x;  // constant pointer to a (non-constant) int
+                        // myPtr will always point to x
 </code>
@@ Line 138: / Line 140: @@
   * A **pointer to constant data** cannot change the value of what it's pointing to.
   * Can point to different things.
-  * Use the ''const'' keyword to qualify the type being pointed to.
+  * ''const'' keyword qualifies the type being pointed to.
 <code cpp>
@@ Line 150: / Line 152: @@
 ===== Constant pointer to constant data =====
-  * **Constant pointer to constant data** cannot change either "what it is pointing to" nor the value of "what it is pointing to."
+  * **Constant pointer to constant data** cannot change either "what it is pointing to" or the value of "what it is pointing to."
 <code cpp>