Setting color in two different ways @*android:color/color1 vs @android:color/color1

I have seen this example:

@*android:col开发者_高级运维or/secondary_text_light

What's that * asterisk doing there? What is the difference when using or not?

As far as I know in Android XML it is supposed to be a wildcard, replacing any number, but it seems an odd placement to me.

There is nothing about it in the documentation or guide, other than here.

Perhaps it is a bug or mistake that doesn't cause compilation errors.