[Feat]: Support hex values

[timgremore]

Supporting hex values in Swift requires an extension (example implementation).

Updates to the rules parser would be needed to recognize:

.foregroundStyle(Color(hex: 0x0d98ba))

[bcardarella]

@carson-katri can you provide the SwiftUI hex syntax that we should support? Just looking in a few places and I see different numerical types:

https://mariusschulz.com/blog/numbers-and-numeric-types-in-swift#numeric-literals

let decimal = 42        // 42 = 4 * 10 + 2 * 1
let binary = 0b101010   // 42 = 1 * 32 + 1 * 8 + 1 * 2
let octal = 0o52        // 42 = 5 * 8 + 2 * 1
let hexadecimal = 0x2A  // 42 = 2 * 16 + 10 * 1

and for hex itself I see what looks like more than one implementation. The typical 0xNNNN but I also see what appears to be some hex arithmatic that is common to see, especially in the context of colors?

[bcardarella]

oh wait wait wait... I missed the original context here. So @timgremore wants to enable hex colors. Maybe we should just bake this into the client so it's on by default?

[carson-katri]

SwiftUI doesn't have built-in support for hex colors. Swift supports writing numbers in hex format, as well as binary and octal as you mentioned. But using these numbers for color values isn't something built-in to SwiftUI.

[carson-katri]

This is actually possible if you use an attribute reference. Colors can be loaded by system name, hex string, or asset catalog name.

<Rectangle
  style='foregroundStyle(attr("color"))'
  color="#FF0000"
/>