diff --git a/src/bin/main.rs b/src/bin/main.rs
index d2a5faa..908da89 100644
--- a/src/bin/main.rs
+++ b/src/bin/main.rs
@@ -14,6 +14,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
+#![feature(type_alias_impl_trait)]
 
 use rustyline::error::ReadlineError;
 use rustyline::Editor;
diff --git a/src/lib.rs b/src/lib.rs
index 97caf87..f1b6570 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -15,6 +15,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#![feature(type_alias_impl_trait)]
+
 mod segment;
 mod lex;
 mod func;
diff --git a/src/vars.rs b/src/vars.rs
index 833bfb7..0500ee3 100644
--- a/src/vars.rs
+++ b/src/vars.rs
@@ -21,7 +21,7 @@ use std::collections::HashMap;
 use std::env;
 use crate::segment::{Ctr, Ast, ast_to_string};
 use crate::eval::eval;
-use crate::func::{Function, Operation, Args, FTable};
+use crate::func::{Function, Operation, InternalOperation, Args, FTable};
 /* Mapping between a string token and a tree of Segments
  * The string token can be found in any Ctr::Symbol value
  * it is expected that the trees stored are already evaluated
@@ -45,53 +45,58 @@ pub fn get_export(env_cfg: bool) -> Function {
         loose_syms: true,
         eval_lazy: true,
         args: Args::Lazy(2),
-        function: Operation::Internal(
-            |a: Ast, b: Rc<RefCell<VTable>>, c: Rc<RefCell<FTable>>| -> Ctr {
-                let inner = a.borrow_mut();
-                match &inner.car {
-                    Ctr::Symbol(identifier) => {
-                        match &inner.cdr {
-                            Ctr::Seg(tree) => {
-                                match eval(tree.clone(), b.clone(), c.clone(), false) {
-                                    Ok(seg) => {
-                                        match seg {
-                                            Ctr::Seg(val) => {
-                                                let val_tmp = val.borrow().clone();
-                                                define(b, identifier.to_string(), Rc::new(val_tmp.car));
-                                                if env_cfg {
-                                                    match val_tmp.car {
-                                                        Ctr::Symbol(s)  => env::set_var(identifier, s),
-                                                        Ctr::String(s)  => env::set_var(identifier, s),
-                                                        Ctr::Integer(i) => env::set_var(identifier, format!("{}", i)),
-                                                        Ctr::Float(f)   => env::set_var(identifier, format!("{}", f)),
-                                                        Ctr::Bool(b)    => env::set_var(identifier, format!("{}", b)),
-                                                        Ctr::Seg(c)     => env::set_var(identifier, ast_to_string(c)),
-                                                        Ctr::None       => ()
-                                                    }
-                                                }
-                                            },
+        function: Operation::Internal(get_export_callback(env_cfg)),
+    };
+}
 
-                                            _ => eprintln!("impossible args to export")
+fn get_export_callback(env_cfg: bool) -> InternalOperation {
+    |a: Ast, b: Rc<RefCell<VTable>>, c: Rc<RefCell<FTable>>| -> Ctr {
+        let inner = a.borrow_mut();
+        match &inner.car {
+            Ctr::Symbol(identifier) => {
+                match &inner.cdr {
+                    Ctr::Seg(tree) => {
+                        match eval(tree.clone(), b.clone(), c.clone(), false) {
+                            Ok(seg) => {
+                                match seg {
+                                    Ctr::Seg(val) => {
+                                        let val_tmp = val.borrow().clone();
+                                        define(b, identifier.to_string(), Rc::new(val_tmp.car));
+                                        if env_cfg {
+                                            match val_tmp.car {
+                                                Ctr::Symbol(s)  => env::set_var(identifier, s),
+                                                Ctr::String(s)  => env::set_var(identifier, s),
+                                                Ctr::Integer(i) => env::set_var(identifier, format!("{}", i)),
+                                                Ctr::Float(f)   => env::set_var(identifier, format!("{}", f)),
+                                                Ctr::Bool(b)    => env::set_var(identifier, format!("{}", b)),
+                                                Ctr::Seg(c)     => env::set_var(identifier, ast_to_string(c)),
+                                                Ctr::None       => ()
+                                            }
                                         }
                                     },
 
-                                    Err(e) => eprintln!("couldnt eval symbol: {}", e)
+                                    _ => eprintln!("impossible args to export")
                                 }
                             },
 
-                            Ctr::None => {
-                                (*b).borrow_mut().remove(identifier);
-                            },
-
-                            _ => eprintln!("args not in standard form")
+                            Err(e) => eprintln!("couldnt eval symbol: {}", e)
                         }
                     },
 
-                    _ => eprintln!("first argument to export must be a symbol")
-                }
+                    Ctr::None => {
+                        (*b).borrow_mut().remove(identifier);
+                        if env_cfg {
+                            // TODO: unset variable
+                        }
+                    },
 
-                return Ctr::None;
-            }
-        )
-    };
+                    _ => eprintln!("args not in standard form")
+                }
+            },
+
+            _ => eprintln!("first argument to export must be a symbol")
+        }
+
+        return Ctr::None;
+    }
 }