On 5 Dec 2008, at 13:40, Andrew Wagner wrote:
Hi all,
public interface IEngine {
void foo();
void bar(string bah);
...
}
public class Program {
public void Run(IEngine engine){
while(true){
string command = GetLine();
if (command.startsWith("foo")){
engine.foo();
} else if (command.startsWith("bar")){
engine.bar(command);
...
else break;
}
In other words, I want to provide the same UI across multiple
implementations of the engine that actually processes the commands.
class IEngine a where
foo :: a -> String
bar :: a -> String -> String
run :: IEngine a => a -> IO ()
run x = interact (unlines . processCommand x . lines)
processCommand e c
| "foo" `isPrefixOf` c = foo e
| "bar" `isPrefixOf` c = bar e c
That should about do it.
Bob
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