Parse bindingRedirects with Linq2Xml

bindingredirects.fsx

// Find binding-redirects with linq-to-xml from a .config file. 
// This might be useful for then parsing config-changes e.g. by System.Linq.Enumerable.Except

#r @"System.Xml.Linq.dll"
open System.Xml.Linq
let parseBindingRedirects (filename:string) =
    let xn s = XName.Get(s,"urn:schemas-microsoft-com:asm.v1")
    let xml = XDocument.Load filename
    let depAssemblies = xml.Descendants(xn "dependentAssembly")
    seq {
        for dependentAssembly in depAssemblies do
            let name =
                dependentAssembly.Elements()
                |> Seq.tryFind(fun e -> e.Name.LocalName = "assemblyIdentity")
                |> Option.map(fun e -> 
                    e.Attributes()
                    |> Seq.tryFind(fun a -> a.Name.LocalName = "name") 
                    |> Option.map(fun v -> v.Value)
                    ) |> Option.flatten
            let bd = 
                dependentAssembly.Elements()
                |> Seq.tryFind(fun e -> e.Name.LocalName = "bindingRedirect")
            let oldVersion =
                bd |> Option.map(fun b -> 
                    b.Attributes() 
                    |> Seq.tryFind(fun a -> a.Name.LocalName = "oldVersion") 
                    |> Option.map(fun v -> v.Value)) |> Option.flatten
            let newVersion =
                bd |> Option.map(fun b -> 
                    b.Attributes() 
                    |> Seq.tryFind(fun a -> a.Name.LocalName = "newVersion") 
                    |> Option.map(fun v -> v.Value)) |> Option.flatten
            match name, oldVersion, newVersion with
            | Some n, Some ov, Some nv -> yield n, ov, nv
            | _ -> ()
    } |> Seq.distinct |> Seq.toList