// ${number} issue type A<T> = T extends `${infer U}.${infer V}` ? U | V : never type B = A<`test.1024`>; // This will be "test" | "1024" as expected type C = A<`test.${number}`>; // Expected "test" | `${number}` or "test" | number but this will be never type D<T> = T extends `${infer U}.${number}` ? U : never type E = D<`test.1024`>; // This will be "test" as expected type F = D<`test.${number}`>; // Expected "test" but this will be never // ${string} issue type G<T> = T extends `${infer U}.${infer V}` ? U | V : never type H = G<`test.hoge`>; // This will be "test" | "hoge" as expected type I = G<`test.${string}`>; // Expected "test" | `${string}` or "test" | string but this will be never type J<T> = T extends `${infer U}.${string}` ? U : never type K = J<`test.hoge`>; // This will be "test" as expected type L = J<`test.${string}`>; // Expected "test" but this will be never