Add debugging interface.

src/api/run.rs

@@ -44,8 +44,10 @@ impl Engine {
     /// Evaluate an [`AST`] with own scope, returning any error (if any).
     #[inline]
     pub fn run_ast_with_scope(&self, scope: &mut Scope, ast: &AST) -> RhaiResultOf<()> {
+        let state = &mut EvalState::new();
         let global = &mut GlobalRuntimeState::new();
-        let mut state = EvalState::new();
+        #[cfg(feature = "debugging")]
+        global.debugger.activate(self.debugger.is_some());
         global.source = ast.source_raw().clone();
 
         #[cfg(not(feature = "no_module"))]
@@ -64,7 +66,7 @@ impl Engine {
             } else {
                 &lib
             };
-            self.eval_global_statements(scope, global, &mut state, statements, lib, 0)?;
+            self.eval_global_statements(scope, global, state, statements, lib, 0)?;
         }
         Ok(())
     }