stringMatch_kata.fs

module Functional_Kats_Kata =

    type PatternType = 
        | Asterisk
        | Question
        | None

    let findPattern (input:string) (pattern:string) patternType =
        match patternType with
        | Asterisk ->      
            let searchString = (pattern.Split [| '*' |]).[0]
            input.StartsWith searchString // seems a little imperative
        | Question ->
            let searchString = (pattern.Split [| '?' |]).[0]
            input.StartsWith searchString && 
                (input.Length = searchString.Length || input.Length = searchString.Length + 1)            
        | None -> false

    let searchPattern (inputArray:string list) (pattern: string) =
        // Good use case for pattern match? Better off using if statement
        let patternType = 
            match pattern.IndexOf "*", pattern.IndexOf '?' with
            | -1, -1 -> None
            | _, -1 -> Asterisk
            | -1, _ -> Question
            | _, _ -> None

        inputArray 
            |> Seq.filter (fun input -> findPattern input pattern patternType) 
            |> Seq.iter (fun i -> printfn "%s" i)

    let searchInput = [ "crisis"; "criteria"; "crisantemo"; "crisix"; "crisi" ]
    searchPattern searchInput "crisi?"
    searchPattern searchInput "crisi"
    searchPattern searchInput "cri*"