In LISP, code the macro, SELECT, which uses the following syntax:

(select expr

(when (valueList1)

(stmt11)

...

(stmt1N) )

(when (valueList2)

(stmt21)

...

(stmt2N) )

...

(default

(stmtd1)

(stmtd2)

...

(stmtdN) ) )

Example:

(select grade

(when (A B)

(setf good (+ 1 good))

(print "doing well")

)

(when (C)

(print "average")

)

(when (D F)

(setf bad (+ bad 1))

(print "oh no")

)

(default

(print (list "unknown value=" grade))

)

)

If the value of expr matches a value in a valueList, each of the corresponding stmt expressions are executed (i.e., eval). The result of the select would be the last stmtn executed.

If the value of expr didn't match a value in any of the valueList and a default is provided, each of the stmt(s) corresponding to the default are executed. The result of the select would be the last stmtn executed.

If the value of expr didn't match a value in any of the valueList and a default is not provided, switch should return NIL.

Note that the values in each valueList are not evaluated.