3 minutes, 42 seconds | The Order of Evaluation - slide 17 : 26 |

Practical implications

We will here describe the practical consequences of the theoretical results mentioned on the previous page

- During the evaluation of an expression, it will never be necessary to backtrack the evaluation process in order to reach a normal form.
- An expression cannot be converted to two different normal forms (modulo alpha conversions, of course).
- If an expression
*e*somehow can be reduced to*f*in one or more steps,*f*can be reached by normal order reduction - but not necessarily by applicative order reduction

Normal-order reduction is more powerful than the applicative-order reduction

Scheme and ML uses applicative-order reduction

Haskell is an example of a functional programming language with normal-order reduction