Set of rules to evaluating expressions.
- Normal Evaluation -> Leftmost function occurrence
double (average 2 4)
plus (average 2 4) (average 2 4)
plus (divide (plus 2 4) 2) (average 2 4)
plus (divide 6 2) (average 2 4)
plus 3 (average 2 4)
plus 3 (divide (plus 2 4) 2)
plus 3 (divide 6 2)
plus 3 3
6
- Applicative Evaluation -> Innermost function occurrence.
double (average 2 4)
double (divide (plus 2 4) 2)
double (divide 6 2)
double 3
plus 3 3
6