diff --git a/crates/erg_common/config.rs b/crates/erg_common/config.rs
index 7abf0a93..dfa9d71c 100644
--- a/crates/erg_common/config.rs
+++ b/crates/erg_common/config.rs
@@ -350,6 +350,19 @@ impl Input {
         }
     }
 
+    pub fn try_read(&mut self) -> std::io::Result<String> {
+        match &mut self.kind {
+            InputKind::File(filename) => {
+                let file = File::open(filename)?;
+                read_file(file)
+            }
+            InputKind::Pipe(s) | InputKind::Str(s) => Ok(s.clone()),
+            InputKind::REPL => Ok(GLOBAL_STDIN.read()),
+            InputKind::DummyREPL(dummy) => Ok(dummy.read_line()),
+            InputKind::Dummy => panic!("cannot read from a dummy file"),
+        }
+    }
+
     pub fn read_non_dummy(&self) -> String {
         match &self.kind {
             InputKind::File(filename) => {
diff --git a/crates/erg_compiler/context/register.rs b/crates/erg_compiler/context/register.rs
index 45462dfd..64f266eb 100644
--- a/crates/erg_compiler/context/register.rs
+++ b/crates/erg_compiler/context/register.rs
@@ -51,7 +51,7 @@ use super::instantiate::TyVarCache;
 use super::instantiate_spec::ParamKind;
 
 pub fn valid_mod_name(name: &str) -> bool {
-    !name.is_empty() && name.trim() == name
+    !name.is_empty() && !name.starts_with('/') && name.trim() == name
 }
 
 /// format:
@@ -1762,24 +1762,28 @@ impl Context {
         }
     }
 
-    fn import_erg_mod(&self, __name__: &Str, loc: &impl Locational) -> CompileResult<PathBuf> {
+    fn import_err(&self, __name__: &Str, loc: &impl Locational) -> TyCheckErrors {
         let mod_cache = self.mod_cache();
         let py_mod_cache = self.py_mod_cache();
+        TyCheckErrors::from(TyCheckError::import_error(
+            self.cfg.input.clone(),
+            line!() as usize,
+            format!("module {__name__} not found"),
+            loc.loc(),
+            self.caused_by(),
+            self.similar_builtin_erg_mod_name(__name__)
+                .or_else(|| mod_cache.get_similar_name(__name__)),
+            self.similar_builtin_py_mod_name(__name__)
+                .or_else(|| py_mod_cache.get_similar_name(__name__)),
+        ))
+    }
+
+    fn import_erg_mod(&self, __name__: &Str, loc: &impl Locational) -> CompileResult<PathBuf> {
+        let mod_cache = self.mod_cache();
         let path = match Self::resolve_real_path(&self.cfg, Path::new(&__name__[..])) {
             Some(path) => path,
             None => {
-                let err = TyCheckErrors::from(TyCheckError::import_error(
-                    self.cfg.input.clone(),
-                    line!() as usize,
-                    format!("module {__name__} not found"),
-                    loc.loc(),
-                    self.caused_by(),
-                    self.similar_builtin_erg_mod_name(__name__)
-                        .or_else(|| mod_cache.get_similar_name(__name__)),
-                    self.similar_builtin_py_mod_name(__name__)
-                        .or_else(|| py_mod_cache.get_similar_name(__name__)),
-                ));
-                return Err(err);
+                return Err(self.import_err(__name__, loc));
             }
         };
         if let Some(referrer) = self.cfg.input.path() {
@@ -1790,7 +1794,10 @@ impl Context {
             return Ok(path);
         }
         let mut cfg = self.cfg.inherit(path.clone());
-        let src = cfg.input.read();
+        let src = cfg
+            .input
+            .try_read()
+            .map_err(|_| self.import_err(__name__, loc))?;
         let mut builder =
             HIRBuilder::new_with_cache(cfg, __name__, self.shared.as_ref().unwrap().clone());
         match builder.build(src, "exec") {
@@ -1942,7 +1949,10 @@ impl Context {
             return Ok(path);
         }
         let mut cfg = self.cfg.inherit(path.clone());
-        let src = cfg.input.read();
+        let src = cfg
+            .input
+            .try_read()
+            .map_err(|_| self.import_err(__name__, loc))?;
         let mut builder = HIRBuilder::new_with_cache(
             cfg,
             self.mod_name(&path),
diff --git a/crates/erg_compiler/declare.rs b/crates/erg_compiler/declare.rs
index b95f0bd7..09e5221d 100644
--- a/crates/erg_compiler/declare.rs
+++ b/crates/erg_compiler/declare.rs
@@ -40,7 +40,7 @@ impl ASTLowerer {
         } else {
             None
         };
-        let chunk = self.declare_chunk(body.block.remove(0))?;
+        let chunk = self.declare_chunk(body.block.remove(0), true)?;
         let py_name = if let hir::Expr::TypeAsc(tasc) = &chunk {
             enum_unwrap!(tasc.expr.as_ref(), hir::Expr::Accessor)
                 .local_name()
@@ -645,12 +645,13 @@ impl ASTLowerer {
         }
     }
 
-    fn declare_chunk(&mut self, expr: ast::Expr) -> LowerResult<hir::Expr> {
+    fn declare_chunk(&mut self, expr: ast::Expr, allow_acc: bool) -> LowerResult<hir::Expr> {
         log!(info "entered {}", fn_name!());
         match expr {
             ast::Expr::Literal(lit) if lit.is_doc_comment() => {
                 Ok(hir::Expr::Lit(self.lower_literal(lit)?))
             }
+            ast::Expr::Accessor(acc) if allow_acc => Ok(hir::Expr::Accessor(self.lower_acc(acc)?)),
             ast::Expr::Def(def) => Ok(hir::Expr::Def(self.declare_def(def)?)),
             ast::Expr::TypeAscription(tasc) => Ok(hir::Expr::TypeAsc(self.declare_ident(tasc)?)),
             ast::Expr::Call(call)
@@ -674,7 +675,7 @@ impl ASTLowerer {
         let mut module = hir::Module::with_capacity(ast.module.len());
         let _ = self.module.context.preregister(ast.module.block());
         for chunk in ast.module.into_iter() {
-            match self.declare_chunk(chunk) {
+            match self.declare_chunk(chunk, false) {
                 Ok(chunk) => {
                     module.push(chunk);
                 }
diff --git a/crates/erg_compiler/lower.rs b/crates/erg_compiler/lower.rs
index 8c00357b..8cde11f0 100644
--- a/crates/erg_compiler/lower.rs
+++ b/crates/erg_compiler/lower.rs
@@ -591,7 +591,7 @@ impl ASTLowerer {
         ))
     }
 
-    fn lower_acc(&mut self, acc: ast::Accessor) -> LowerResult<hir::Accessor> {
+    pub(crate) fn lower_acc(&mut self, acc: ast::Accessor) -> LowerResult<hir::Accessor> {
         log!(info "entered {}({acc})", fn_name!());
         match acc {
             ast::Accessor::Ident(ident) => {