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--- guides:programstyle:constants [2020/07/24 12:05] – wikiadmin
+++ guides:programstyle:constants [2024/07/25 15:01] (current) – external edit 127.0.0.1
@@ Line 49: / Line 49: @@
 Note this is a very bad use.  If the user decided to change MAX_ITEMS, a new bug would be introduced into the code.
-In the o
+In the last example, a programmer might be tempted to employ the following definition
+<code c++>
+const int TWENTY = 20;
+</code>
-Unless otherwise instructed, a single prompt, the
+This is unacceptable for multiple reasons.
+  * TWENTY is no more informative than 20.
+  * If the value of the constant changed, the programmer might be tempted to produce the following totally unacceptable code
+    * <code c++>
+const int TWENTY = 35;
+</code>
+Unless otherwise instructed, single use constants are usually not named unless they provide clarity to the program.  Examples include a prompt used one time or an arbitrary field width.
+The following is probably not necessairy
+<code c++>
+const int FIRST_FIELD_WITDTH = 20;
+const string FIRST_PROMPT = "Enter your Age";
+...
+cout << setw(FIRST_FIELD_WIDTH) << FIRST_PROMPT << endl;
+</code>