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Missing stackframes in debugger
f#

I have some pure recursive F# code (rewrite rule) and I'm having trouble debugging.
It appears that several internal stackframes in the middle of the callstack are replaced by "[External Code]".
I'm not sure why this would happen, as it's all diect recursion into the same fn - but it's making things extrememly hard to deubug. I'm in Debug mode and have tail-calls off.
Anyone else seeing this?
thanks

.

Uncheck

Tools\Options\Debugging\Enable Just My Code

That's what 'External Code' is. You're probably in FSharp.Core.dll.

Try putting a breakpoint on the printf line below, and debugging, and inspect the call stack with the above VS option checked and unchecked to see the difference.

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let lol = [ [1;2;3]; [4;5;6]; [7;8;9] ]

let G x = 
    printfn "%d" x
    
let rec F l =
    match l with
    | [] -> ()
    | h::t -> 
        h |> List.iter G
        F t
                
F lol
By on 3/18/2010 10:49 AM ()

I should have caught that- thanks.

Seems like a bizzare option to have on by default - I'd think anyone who is capable of debugging wants to see what's really going on, and then can be given the choice of a more succinct view.

Having "external" code collapsed in a tree I can see - or at least a tooltip on "external code" with the collapsed stack and a button to toggle the option - or a summary like, "External code (FSharp.Core.dll : List.Map)"

By on 3/18/2010 11:34 AM ()

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