Using component property's value as variable

How nice would it be if a value of a component’s property can be used as value of a different property of the same component?

Let’s say you’re designing a screen where the user can change the size of another component by pressing a button. The button component not only has a label, but also an icon, via a property each icon has its own value. As you name those values carefully, you want to use those values as a variable or the button labels. In the ideal world you’d type something like $size as value for the text property of the button’s label, and it would change the value of the text property after selecting a value of the other property, for every individual button (because why type it every time?)