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@kunjee17
Last active October 25, 2015 18:12
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[<CLIMutableAttribute>]
[<AliasAttribute("hello")>]
type HelloDb =
{ Name : string }
[<LiteralAttribute>]
let connStr = "Server = localhost; Port = 5432; Database = database; User Id = username; password = password;"
let dbfactory = OrmLiteConnectionFactory(connStr, PostgreSqlDialect.Provider)
let agent =
MailboxProcessor.Start(fun inbox ->
//let db = dbfactory.Open(); persistance open connection.
let rec messageLoop() =
async {
let! (msg : Hello) = inbox.Receive()
do use db = dbfactory.Open()
//do some processing
db.InsertAsync(msg)
|> Async.AwaitTask
|> ignore
printfn "%A" msg.Name
do! Async.Sleep(rnd.Next(100, 1000))
return! messageLoop()
}
messageLoop())
agent.Post {Name:"Kunjan"}
//How can use this agent to insert data. Because if they are queue I guess it is ok to use persistance open connection. Here I am not doing it
//but I guess that very much possible
@swlaschin
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As Isaac said, you can use a using expression, or alternatively, create a new scope by indenting with a do at the top, like this:

let rec disposingLoop n = 
    do
        // start new scope
        use db = newDisposable n
        printfn "inside loop %i" n
    if n = 0 then
        printfn "Loop stopped" 
    else
        disposingLoop (n-1) 

disposingLoop 5

Output is:

inside loop 5
disposing 5
inside loop 4
disposing 4
inside loop 3
disposing 3
inside loop 2
disposing 2
inside loop 1
disposing 1
inside loop 0
disposing 0
Loop stopped

@kunjee17
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Author

@swlaschin and @isaacabraham how can I use do keyword within async keyword. It is giving me compilation error.

@isaacabraham
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If to await an Async, it's do!

@kunjee17
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@isaacabraham I tried that also. It also didn't work. Can you please give example in context of gist? It will be great help.

@kunjee17
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@swlaschin and @isaacabraham. I guess I make it working. Please have a look that if it is good as per code. It is working now without closing connection.

And ya we can't use any bang thing in do clause. means that do! will be outside of that clause. Or anything that I should be asynced...

PS: ref - http://stackoverflow.com/questions/7433426/f-async-dispose

@swlaschin
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Looks good to me. That SO question has good answers too!

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