The case statement. Let us investigate the case statement, whose semantics is defined in section 13.1.9.

(a) Show how the semantic rules of case can be derived from the rules for local and if.

(b) In the first rule for the case, we could have explicitly introduced variables for the Xi by

Do the rules lead to the same possible executions? What are the differences (if any)?

(c) It is possible to write an if statement in terms of a case statement. How? This implies that case could have been put in the kernel language instead of if, and if could have been defined as a linguistic abstraction.