Syntax Colorizer doesn't recognise computation expressions with generic types

[KevinRansom]

Originally opened at CodePlex by ashtonkj

The default syntax highlighter will highlight a computation expression without a generic type parameter, but once a generic type parameter is provided then the syntax highlighter will not colour the computation expression. See the following code for example (In the default Visual Studio dark theme ceBoolBuilder is coloured blue, but ceBuilder<System.DateTimeKind> is not):

type TestCE<'T>() =
    member this.ReturnFrom(value) =
        if System.String.IsNullOrEmpty(value) then
            None
        else
            let typeT = typeof<'T>
            if typeT.IsEnum then
                box (System.Enum.Parse(typeT, value)) |> Some
            else if typeT = typeof<bool> then
                box (bool.Parse(value)) |> Some
            else None

let ceBuilder<'T> = TestCE<'T>()
let ceBoolBuilder = TestCE<bool>()

let exampleIncorrect = ceBuilder<System.DateTimeKind> { return! System.DateTimeKind.Local.ToString() }
let exampleCorrect = ceBoolBuilder { return! "true" }
Image

comments
coza99 wrote Sep 3, 2014 at 3:54 AM [x]
This is also true if the builder function is parameterized. Taking the case from above an example

type TextCE<'T>(name:string) = 
        ..........
let ceBuilder<'T> name = TestCE<'T>(name)

[latkin]

@ashtonkj do you still have the image from when you originally filed this one? Seems like it's broken now: http://namelessinteractive.com/media/Example.png

[ashtonkj]

Hi @latkin. Image attached.Sorry for the delay, just installed windows 10 and broke everything else (not window's fault, driver issue caused me to have to do a clean install). As you can see the parameterised ceBuilder<System.DateTimeKind> doesn't highlight as a keyword, whereas the ceBoolBuilder does.

[dsyme]

FWIW this was a known limitation when we implemented this colorization feature.

[ashtonkj]

@dsyme does that mean it won't be changed?

[dsyme]

@ashtonkj Not necessarily! It may not be that hard

[dsyme]

But would reduce the priority

[dsyme]

Closing this as "by design" - perhaps Visual F# Power Tools can do something here.