cfg_match

Cargo.lock

@@ -3,5 +3,5 @@
 version = 3
 
 [[package]]
-name = "haha"
+name = "uwu"
 version = "0.1.0"

Cargo.toml

@@ -1,5 +1,5 @@
 [package]
-name = "haha"
+name = "uwu"
 version = "0.1.0"
 edition = "2021"
 

src/cfg_match.rs

@@ -0,0 +1,58 @@
+#[macro_export]
+macro_rules! cfg_match {
+    () => {};
+    (_ => { $($tt:tt)* }) => {
+        $($tt)*
+    };
+    (
+        $head_pattern:meta => { $($head_body:tt)* }
+        $($rest:tt)*
+    ) => {
+
+        #[cfg($head_pattern)]
+        $crate::cfg_match! { _ => { $($head_body)* } }
+
+        #[cfg(not($head_pattern))]
+        $crate::cfg_match! {
+            $($rest)*
+        }
+    };
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn correct_one_selected() {
+        crate::cfg_match! {
+            any() => {
+                panic!();
+            }
+            all() => {
+
+            }
+            any() => {
+                panic!();
+            }
+        }
+    }
+
+    #[test]
+    fn underscore() {
+        crate::cfg_match! {
+            _ => {}
+        }
+    }
+
+    #[test]
+    fn fallback() {
+        crate::cfg_match! {
+            any() => {
+                panic!();
+            }
+            any() => {
+                panic!();
+            }
+            _ => {}
+        }
+    }
+}