You saw in this chapter (and in Exercise 8.14) that it makes sense to have an if-expression in a language. (a) Does it make sense to have a while-expression; that is, can a while-expression return a...

You saw in this chapter (and in Exercise 8.14) that it makes sense to have an if-expression in a language.

(a) Does it make sense to have a while-expression; that is, can a while-expression return a value, and if so, what value?

(b) Does it make sense to have a case-or switch-expression; that is, can a case-expression return a value, and if so, what value?

 (c) Does it make sense to have a do-or repeat-expression; that is, can a do-expression return a value, and if so, what value?

Exercise 8.14