Exercises in Programming Style–Declared Intentions

NOTE : read the rest of the series, or check out the source code.

If you enjoy read­ing these exer­cises then please buy Crista’s book to sup­port her work.

Fol­low­ing on from the last post, we will look at the Declared Intentions style today.

Style 23 — Declared Intentions

Constraints

• Existence of a run-time typechecker.
• Procedures and functions declare what types of arguments they expect.
• If callers send arguments of types that aren’t expected, the procedures/functions are not executed.

The problem of type checking is a solved problem in statically typed languages, so by programming in F# there’s almost nothing we need to really do for this style.

Using the same solution from the Pipeline (aka functional) style, I have added a few explicit type declarations to better comply with the constraints.

You can find the source code for this exercise here.