| make-selector-function-session - Example usages of the function make-selector-function. | Lecture 2 - slide 16 : 35 Program 2 |
1> (define first (make-selector-function 1 "first"))
2> (first '(a b c))
a
3> (first '())
The selector function first:
The list () is is too short for selection.
It must have at least 1 elements.
>
4> (define (make-person-record firstname lastname department)
(list 'person-record firstname lastname department))
5> (define person-record
(make-person-record "Kurt" "Normark" "Computer Science"))
6> (define first-name-of
(make-selector-function 2 "first-name-of"))
7> (define last-name-of
(make-selector-function 3 "last-name-of"))
8> (last-name-of person-record)
"Normark"
9> (first-name-of person-record)
"Kurt"