WIG Pattern.OptionalFields accessing wrong property

[dvdkon]

When a property is generated by Pattern.OptionalFields, accessing the "...Opt" variant should translate to accessing the base-name property in JavaScript. Due to a bug, the resulting JS code accesses the non-existent "...Opt" property.

Sample WIG F# code:

let C1 =
    Class "C1"
    |+> Pattern.OptionalFields [
        "field", T<int>
    ]

Resultant .DLL decompiled to C#:

public class C1 {
	public Optional<int> FieldOpt {
		[Inline("$this.fieldOpt")]
		get {
			throw new NotImplementedException();
		}
		[Inline("$wsruntime.SetOrDelete($this, 'fieldOpt', $value)")]
		set {
			throw new NotImplementedException();
		}
	}

	public int Field {
		[Inline("void ($this.field = $value)")]
		set {
			throw new NotImplementedException();
		}
	}
}

Note how the Inline annotation contains fieldOpt, when it should contain just field.

I tried to fix this myself, but I couldn't get WebSharper to build. All it should take as far as I know is WithSourceName in the function.

[granicz]

@dvdkon Thanks for the report! First and foremost is to figure out why the repo wouldn't build for you. Could you post the error you are seeing on a separate ticket? Thanks!

[dvdkon]

All right, here's the issue number: #1118

[Jand42]

@dvdkon Thanks for the report, fix will be in next release soon.
Workaround:
Define OptionalFields helper for yourself, it's just a convenience tool built upon other public WIG API operators and functions.

    let OptionalFields (optional: seq<string * Type.Type>) =
        Instance [
            for (n, t) in optional do
                yield n =! t :> _
                let sn =
                    let name = n.Replace('.', '_')
                    name.Substring(0, 1).ToUpper() + name.Substring 1 + "Opt"
                yield n =@ !?t |> WithSourceName sn :> _
        ]

[Jand42]

@dvdkon Fix is part of https://github.com/dotnet-websharper/core/releases/tag/4.7.0.423