"What" prevailing over "how"
This property of the functional solution mental process is easier to demonstrate with an example. I paraphrase here the great one from the early days of F# that's been used by several insiders previously. Imagine yourself in Starbucks for Caffè Americano.
The "how" approach would be to give detailed instructions such as:
- Take a roasted coffee
- Brew two espresso shots
- Top them with hot water to produce a layer of crema
- Put it into a cap of 12 oz size
The "what" approach would be to just ask "May I have a tall Caffè Americano?".
The second approach is evidently much more succinct and minimizes an opportunity of getting a result that deviates from the desired one. If you revisit now our three preceding solutions you should spot this property there.
