simple code to find a word in a string

i try this code from book but get an error, can somebody help me?

#if INTERACTIVE
#r "FSharp.PowerPack.dll";;
#r "FSharp.PowerPack.Compatibility.dll";;
#endif

open System
ope开发者_开发知识库n System.IO
open System.Collections.Generic
open Microsoft.FSharp.Collections.Tagged

let str = "This is a string, try to break it buddy!\nfind!"

let isWord (words) = 
    let wordTable = Set.Create(words)
    fun w -> wordTable.Contains(w)

For Set.Create the compiler says:

Multiple types exist called 'Set', taking different numbers of generic parameters. Provide a type instantiation to disambiguate the type resolution, e.g. 'Set<_>'.

What does it mean?

The problem is that there are two types named Set: F#'s one and the one in the PowerPack (actually there are three types, but that doesn't matter). In your case the F# Set type will do just fine so you don't need the tagged Set from the PowerPack. Try the following code:

open System

let str = "This is a string, try to break it buddy!\nfind!"

let isWord words = 
    let wordTable = new Set(words) // or you can use Set.ofArray words
    fun w -> wordTable.Contains(w)

I think you should try something like

Set<string>.Create()

to define the datatypes that will be stored in the set.