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@hodzanassredin
Created September 25, 2011 19:57
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Sample of file system TypeProvider
namespace FilesTypeProvider
open System.Reflection
open Microsoft.FSharp.Core.CompilerServices
open Samples.FSharpPreviewRelease2011.ProvidedTypes
open System.Text.RegularExpressions
[<TypeProvider>]
type public CheckedFilesProvider() as this =
inherit TypeProviderForNamespaces()
let baseTy = typeof<obj>
let rec addMembers (path:string) (ownerTy:ProvidedTypeDefinition) =
ownerTy.AddXmlDoc "A strongly typed interface to the directory '%s'"
let dir = new System.IO.DirectoryInfo(path)
let pathField = ProvidedLiteralField("Path", typeof<string>, dir.FullName);
pathField.AddXmlDoc "Full path to fullName"
ownerTy.AddMember pathField
for sub in dir.EnumerateDirectories() do
let subTy = ProvidedTypeDefinition(
typeName = sub.Name.Replace(' ','_'),
baseType = Some baseTy,
HideObjectMethods = true)
let pathField = ProvidedLiteralField("Path", typeof<string>, sub.FullName)
pathField.AddXmlDoc "Full path to fullName"
subTy.AddMember pathField
addMembersSafe sub.FullName subTy
ownerTy.AddMember subTy
for file in dir.EnumerateFiles() do
let subTy = ProvidedTypeDefinition(
typeName = file.Name.Replace(' ','_'),
baseType = Some baseTy,
HideObjectMethods = true)
let pathField = ProvidedLiteralField("Path", typeof<string>, file.FullName)
pathField.AddXmlDoc "Full path to fullName"
subTy.AddMember pathField
ownerTy.AddMember subTy
and addMembersSafe (path:string) (ownerTy:ProvidedTypeDefinition) =
try
addMembers path ownerTy
with | exn ->
()
let thisAssembly = Assembly.GetExecutingAssembly()
let rootNamespace = "FilesTypeProvider"
let staticParams = [ProvidedStaticParameter("path", typeof<string>)]
let fileTy = ProvidedTypeDefinition(thisAssembly, rootNamespace, "FileTyped", Some baseTy)
do fileTy.DefineStaticParameters(
parameters=staticParams,
instantiationFunction=(fun typeName parameterValues ->
match parameterValues with
| [| :? string as path |] ->
let ty = ProvidedTypeDefinition(
assembly = thisAssembly,
namespaceName = rootNamespace,
typeName = typeName,
baseType = Some baseTy,
HideObjectMethods = true)
addMembersSafe path ty
ty
| _ -> failwith "unexpected parameter values"))
do this.AddNamespace(rootNamespace, [fileTy])
[<TypeProviderAssembly>]
do ()
@hodzanassredin
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To use:

r @"C:\Users\hodza\Documents\Visual Studio 11\Projects\FileSystemTypeProvider\FileSystemTypeProvider\bin\Debug\FileSystemTypeProvider.dll"

open FilesTypeProvider

type T = FileTyped< @"C:\Users\hodza\Documents">

printf "Dir path = %s" T.Visual_Studio_2010.Code_Snippets.Nemerle.My_Code_Snippets.Path
.

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