Investigate Task.await behaviour in rocci-bird

[lukewilliamboswell]

Investigate why the two below are not equal.

The only change is the line collided <- collidedTask |> Task.await to Task.await collidedTask \collided ->

    List.walk collisionPoints (Task.ok Bool.false) \collidedTask, { x, y } ->
        collided <- collidedTask |> Task.await
        if collided then
            Task.ok Bool.true
        else
            point = {
                x: Num.toU8 (playerX + x),
                y: Num.toU8 (playerY + y),
            }
            color = W4.getPixel! point
            Task.ok (color != Color1)

    List.walk collisionPoints (Task.ok Bool.false) \collidedTask, { x, y } ->
        Task.await collidedTask \collided ->
            if collided then
                Task.ok Bool.true
            else
                point = {
                    x: Num.toU8 (playerX + x),
                    y: Num.toU8 (playerY + y),
                }
                color = W4.getPixel! point
                Task.ok (color != Color1)

── TYPE MISMATCH in examples/rocci-bird.roc ────────────────────────────────────

This expression is used in an unexpected way:

407│>      List.walk collisionPoints (Task.ok Bool.false) \collidedTask, { x, y } ->
408│>          Task.await collidedTask \collided ->
409│>              if collided then
410│>                  Task.ok Bool.true
411│>              else
412│>                  point = {
413│>                      x: Num.toU8 (playerX + x),
414│>                      y: Num.toU8 (playerY + y),
415│>                  }
416│>                  color = W4.getPixel! point
417│>                  Task.ok (color != Color1)

This walk call produces:

    InternalTask.Task Bool *

But you are trying to use it as:

    {}a

Tip: Type comparisons between an opaque type are only ever equal if
both types are the same opaque type. Did you mean to create an opaque
type by wrapping it? If I have an opaque type Age := U32 I can create
an instance of this opaque type by doing @Age 23.


── TYPE MISMATCH in examples/rocci-bird.roc ────────────────────────────────────

Something is off with the body of the onScreenCollided definition:


  

This Task.ok call produces:

    Task {} []

But the type annotation on onScreenCollided says it should be:

    Task Bool []

────────────────────────────────────────────────────────────────────────────────

[lukewilliamboswell]

Update - as a workaround in bocci-bird I've pull the closure out into a helper and that has resolved the issue. But this still seems like an interesting edge case.