F# computation expression for nested Boolean tests?
computation-expression, f#, monads, option-type
Solution
I offered up a conditional workflow in response to a similar problem. I'll copy it here, for reference.
module Condition =
type ConditionBuilder() =
member x.Bind(v, f) = if v then f() else false
member x.Return(v) = v
let condition = ConditionBuilder()
open Condition
let eval() =
condition {
// do some work
do! conditionA
// do some work
do! conditionB
// do some work
do! conditionC
return true
}
As you can see in the comments to my previous answer, not everyone's a fan. But it's interesting nonetheless.
Problem
I think I've got enough understanding of F# monads (workflows) that I see a few places in my code where implementing them makes sense. For example, I've got a function with multiple nested if/thens, i.e. the function should continue only so long as the data pass certain "tests" along the way. I'm familiar with the "maybe" monad, but in all the examples that I've seen, it's coded to operate on `let!` bindings, which I'm not doing. I'm hoping that someone can provide me with an example of the "maybe" workflow tailored for nested Boolean tests, not `let` binds.