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--- guides:programstyle:goto [2020/08/04 14:32] – created wikiadmin
+++ guides:programstyle:goto [2024/07/25 15:01] (current) – external edit 127.0.0.1
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 All of these statements change the flow of control in a c++ program.  They change the behavior of control structures and therefore make it more difficult to understand the final flow of control in a program.  For these reasons, the use of these statements is heavily restricted.
+===== Summary =====
+  * Do not use continue statements
+  * Do not use goto statements
+  * Only use break statements in switch statements
+  * Only use a single return statement per function. It must be the last statement in the function.
+  * All functions should have a return statement.
 ===== goto =====
+The use of a goto statement transfers code to a predefined location in the program.  This can produce code which is difficult to follow and is therefore prohibited by the local style guide.
 ===== continue =====
+The continue statement allows a programmer to skip the remaining statements in a control structure.  When employed in a loop, this will immediately transfer control to the end of the loop, however additional loop iterations may occur.
+The use of continue statements can cause surprising flow of control to those who are unaccustomed to their use.
+The use of continue statements is not permitted in the local style guide.
 ===== break =====
+The break statement causes control to be transferred to the end of the innermost control structure. It can be used to exit a loop without using the normal loop conditional statement.   Such a use will cause those unfamiliar with this programming style to misread the code.
+Break is the primary method to exit a case or set of cases in a switch statement.
+The local style guide prohibits the use of **break** except in switch statements.
 ===== return =====
+Return statements are used to transfer control from a called function to a calling function.  In C++ the return statement may or may not return a value, depending on the function prototype.
+Local convention states that each function should have exactly one return statement and that this statement should be the last line of code in the function.
+Examples  of acceptable use:
+<code c++>
+// note the return for a void function has no argument.
+void PrintHello(void) {
+    cout << hello << endl;
+    return;
+}
+int Square(int n) {
+    return n*n;
+}
+</code>
+A function should not have more than a single return.  The following example does not match the style guide:
+<code c++>
+bool IsPositive(int n) {
+    if (n > 0) {
+       return true;
+    } else {
+       return false;
+    }
+}
+</code>
+For more advanced classes, especially after the student has demonstrated a strong grasp of flow control and logical expressions, the above code **might** be acceptable.  In general, multiple returns should only be employed when the code is extremely simple.  Speciffically, replacing //break// statements in a switch structure with returns meets this criteria, as long as **all** break statements are replaced.
+With instructor approval, the both instances of the given code are acceptable.
+<code c++>
+string DigitName(int n) {
+   string name;
+     switch(n) {
+      case 1: name = "One";
+              break;
+      case 2: name = "Two";
+              break;
+      case 3: name = "Three";
+              break;
+      ...
+   }
+   return name;
+}
+string DigitName(int n) {
+   switch(n) {
+      case 1: return "One";
+      case 2: return "Two";
+      case 3: return "Three";
+      ...
+   }
+   return "";
+}
+</code>
+Please consult your instructor before you use more than one return in a function.