Multiple accessibilities given for property getter or setter is not raised for property

[nojaf]

Get and set properties cannot have different visibility for the getter and setter

Repro steps

Example:

type Foo() =
    member f.X with internal get (key1, key2) = true and private set (key1, key2) value = ()
    member internal f.Y with get (key1, key2) = true and private set (key1, key2) value = ()

Expected behavior

Both X and Y show the same diagnostic (FS0558)

Actual behavior

f.X won't produce any diagnostics and will create an internal getter and setter.

While f.Y will produce

Known workarounds

/

Related information

Local compiler

[T-Gro]

The error works a little diffently.

You can have visiblity:

• "outer" for the entire member
• "inner" just for set
• "inner" just for get

When you mix outer and inner, you get the error you screenshoted
If you omit outer and use two inner ones, they can be as they wish.

This also gets reflected in the IL (just follows the standard the privates in F# become internals in IL, but that's it)

https://sharplab.io/#v2:DYLgZgzgNALiCWwA+BtAPAOQPYFECOArgIbDwwCeAfALoCwAUOtgMJYC2ADkQE7wRYA7GgwocApgAIAYliwAKAJQSAvAwnqJbMWwBGY7hLAA6ABoS1GywHcyAC3P1LTjRwI7SAYwkBzMTAly/FoAaiRKyhIw3ASSFs5EAgAmEhy8AG5EMJIQfgFBYqHAShnAMSoBCkA=

[auduchinok]

A property declaration may also be split into two, so the getter and the setter would be analysed separately.
And then comes the fact that F# allows overloading properties, so we won't even know if two accessor declarations will belong to the same property until after type checking is done.

[0101]

Get and set properties can have different visibility for the getter and setter. But the error message is confusing and should be fixed.