13.14. Objectives of This Chapter

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By the end of this chapter you should have:

1. Learned how to use a namespace to group a number of functions together even if they don't have any associated data;

2. Learned how to write an "endless" loop to execute a section of code an indefinite number of times;

3. Learned how to check numeric input for validity and give the user a reasonable error message if that input is invalid;

4. Learned how to obtain keyboard input without having to wait for the user to hit the Enter key;

5. Learned how to write output on the screen at a particular position;

6. Learned how to clear the screen or an individual line on the screen;

7. Learned how to display part of a list on the screen, scrolling the rest of the list on and off the screen as necessary;

8. Learned how to use the xstring concatenation operator to aid in the formatting of data;

9. Learned how to compare and sort xstring data without regard for case;

10. Learned how to print data on the printer, including the use of the "form feed" character to ensure that any further data sent to the printer will start on a new page;

11. Learned how to delete an item from a list kept in a Vec.