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Option Result library for c#
  • I very much disagree with this, Null Reference Exceptions have been a huge problem in c#. Nullable reference types are a partial fix, but the question of "how do I 'return' an error from a statically typed method" is not answered there.

  • Option Result library for c#
  • The operator being applied to the ResultObject will always resolve to the Generic type that was specified as 'T in IResult<T>. If the function is not successful the resolved value will be whatever value was supplied to the ResultObject constructor, the opt.None property will true and the opt.Some property will be false.

  • Option Result library for c#
  • The example is simplified, but I dislike returning null in my own code. The function will always execute, left or right doesn't matter it's mapped across in the ResultObject class.

    The function must return an IResult<T>, the ResultObject analyzes the IResult<T> checking for IFail or IOk. If it's IOk the value of type T is retrieved from the Value property of the IOk<T> object and returned, the Some property defaults to true. If the IResult<T> is an IFail, Some is set to false, it copies the message from the IFail object into the ResultObject, and returns the value the was supplied to its constructor.

    I'm just sharing something I find useful, and I hope I can make it useful for others as well. Thanks for the questions.

  • Option Result library for c#

    A collection of tools for dealing with nulls, failures and the generic type issues that arise in this domain.

    https://github.com/Andy3432344/SafeResults

    I'm the author, let me know what you think!

    *Edit: updated to show GitHub link, sorry!

    13
    Question regarding generic type and Type
  • Here's a real world side project example of how I handle this situation:

     public IResult<T> GetResourceValue<T>(string path)
        {
            string err = $"{typeof(T).FullName} is not available from this Resource ({nameof(FileSystemResource)})";
    
            switch (typeof(T))
            {
                case Type t when t == typeof(DriveInfo):
                    return (IResult<T>)new Ok<DriveInfo>(BackingValue);
                case Type t when t == typeof(DirectoryInfo):
                    err = $"Directory path invalid: {path}";
                    var dir = new DirectoryInfo(path);
    
                    if (dir.Exists)
                        return (IResult<T>)new Ok<DirectoryInfo>(dir);
                    break;
                case Type t when t == typeof(FileInfo):
                    err = $"File path invalid: {path}";
                    var file = new FileInfo(path);
    
                    if (file.Exists)
                        return (IResult<T>)new Ok<FileInfo>(file);
                    break;
            }
            return new Error<T>(err);
        }
    

    You said elsewhere that it feels like you're doing something wrong if you have to check for every type just to use a Generic. I think you're right in thinking along those lines. There should be a minimal number of types to check, and Ideally limited via a type constraint.

    Here's example that includes a constraint:

        public IResult<T> GetValue<T>() where T : struct =>
            typeof(T) switch
            {
                Type t when t == typeof(int) && value <= int.MaxValue =>
                 (IResult<T>)new Ok<int>((int)value),
                Type t when t == typeof(uint) && value <= uint.MaxValue && value >= uint.MinValue =>
                 (IResult<T>)new Ok<uint>((uint)value),
                Type t when t == typeof(byte) && value <= byte.MaxValue && value >= byte.MinValue =>
                 (IResult<T>)new Ok<byte>((byte)value),
                Type t when t == typeof(sbyte) && value <= (int)sbyte.MaxValue =>
                 (IResult<T>)new Ok<sbyte>((sbyte)value),
                Type t when t == typeof(short) && value <= (int)short.MaxValue =>
                 (IResult<T>)new Ok<short>((short)value),
                Type t when t == typeof(ushort) && value <= ushort.MaxValue =>
                 (IResult<T>)new Ok<ushort>((ushort)value),
                Type t when t == typeof(long) && value <= long.MaxValue =>
                 (IResult<T>)new Ok<long>((long)value),
                Type t when t == typeof(ulong) => (IResult<T>)new Ok<int>((int)value),
                _ => new IntegerError<T>()
            };
    
  • All popular IDEs (and most apps) seem stuck in a single-monitor paradigm. When are we going to get an IDE that sets the bar for working with multiple monitors? For inspiration, look at multi-monitor
  • I use fancy zones for windows, and I have a zone that compromises one 4k screen and half of two others. That zone is for my VS window, two main code panes in the center and one off to each side.

    It doesn't remember the layout of the tool windows... I'll have to look into the save/apply functionality you mentioned.

    I prefer VS over vs-code, but in VS the window/tabs are bulky and slow compared to vs code which makes this all more annoying. First world problems though...

    Edit: using VS 2022 on win 10

  • All popular IDEs (and most apps) seem stuck in a single-monitor paradigm. When are we going to get an IDE that sets the bar for working with multiple monitors? For inspiration, look at multi-monitor
  • Not OP, but in agreement. I like to split out multiple vertical panes in VS, and I put the edges of the panes at the edge of the monitors. It's tedious to position them manually, and different tool windows run when debugging so I have to reposition the pane boundary's again whenever switching between run/design time. It would be nice if it detected the edge of the monitors and kept the scroll bars and break-point column on the correct sides of the split.

  • Kristi Noem Now Banned in More Than 90 Percent of All South Dakota Tribal Lands
  • [their children] don’t have parents who show up and help them.

    [their leadership] focuses on a political agenda more than they care about actually helping somebody’s life look better.

    Every accusation is an admission...

  • Is anyone else stuck on overhead?

    I work for a services company, and we're not getting much right now. Just wanted to ask about work availability across the board.

    7
    Some communities say No Posts

    !error no posts

    I have an active post in vscode right now, which I made in browser, but cannot see anything when viewing the community with Connect. Any ideas?

    2
    FSI Start

    Hi everyone, I'm trying to try out F# via FSI in VS Code (Windows 10)

    I have Ionide for F# installed, and have used it before, but now every time I try to start it I get a message "FSI :Start resulted in an error", it goes on to helpfully report "the option has no value".

    dotnet is in path, dotnet works great. FSI? nothing.

    I also have the .net workload installed for visual studio 2022 (if that matters).

    I started up my Linux VM (KDE Neon) fired up vs codium and tried FSI Start...same error! So no tinkering in f# for me tonight. Does anyone have an idea what's happening, across two environments? Google is no help...

    0
    InitialsDiceBearhttps://github.com/dicebear/dicebearhttps://creativecommons.org/publicdomain/zero/1.0/„Initials” (https://github.com/dicebear/dicebear) by „DiceBear”, licensed under „CC0 1.0” (https://creativecommons.org/publicdomain/zero/1.0/)DR
    DrDeadCrash @programming.dev
    Posts 4
    Comments 211