Add new feature idea to IDEAS.md

IDEAS.md

@@ -0,0 +1,87 @@
+## Enum subsets
+
+i.e. tagging a certain subset of enum cases as and then allowing conversion to/from that subset seamlessly
+
+```
+enum Platform {
+  subset ApplePlatform {
+    func releaseYear() -> Int {
+      switch self {
+        case .macOS: 1998 // made up
+        case .iOS: 2007
+      }
+    }
+  }
+
+  case macOS[ApplePlatform]
+  case iOS[ApplePlatform]
+  case linux
+
+  func name() -> String {
+    switch self {
+      case .macOS: "macOS"
+      case .iOS: "iOS"
+      case .linux: "Linux"
+    }
+  }
+}
+
+func doApple(_ platform: Platform.ApplePlatform) {
+  print("{platform.name()} was released in {platform.releaseYear()}")
+}
+
+switch platform {
+  case .macOS, .iOS:
+    doApple(platform)
+  case .linux:
+    print("Linux has always been released and always will be")
+}
+```
+
+## Enum relabelling
+
+Allow multiple versions of an enum with different labels; I often find myself with multiple
+versions of the same enum for different contexts, and there's tons of annoying glue code
+involved.
+
+```
+enum Direction {
+  case up
+  case down
+  case left
+  case right
+}
+
+enum Edge relabelling Direction {
+  case top[up] // would need to think about this syntax a bit longer
+  case bottom[down]
+  case leading[left]
+  case trailing[right]
+}
+```
+
+## Automatic 'kind' enums
+
+It can be useful to have both data enums and kind enums; yet there's usually a lot of boilerplate involved so
+they're avoided.
+
+```
+enum OSVersion {
+  case macOS(SemVer)
+  case iOS(SemVer)
+  case linux(KernelVersion)
+  case windows(MSVersion)
+}
+
+enum OS = kind OSVersion // syntax needs work
+
+let version: OSVersion = .macOS(SemVer(11, 2, 5))
+let os = OS(version) // OS.macOS
+```
+
+## Follow Rust's lead with separating out conformance `impl`s from basic `impl`s
+
+From my experience with generics in the SwiftCrossUI project, I've found that it's quite common
+for conformances to silently become stale when default implementations are available which can
+cause some pretty subtle bugs. If `impl` blocks for conformances can only define members
+satisfying the conformance requirements then this whole source of bugs is eliminated.

Sources/UtilityMacrosPlugin/UtilityMacrosPlugin.swift

@@ -2,7 +2,7 @@ import SwiftCompilerPlugin
 import SwiftSyntaxMacros
 
 @main
-struct MacroToolkitExamplePlugin: CompilerPlugin {
+struct UtilityMacrosPlugin: CompilerPlugin {
     let providingMacros: [Macro.Type] = [
         WithSpanMacro.self,
         ResultMacro.self,