diff --git a/src/semantic/mod.rs b/src/semantic/mod.rs
index ed460f6..055283d 100644
--- a/src/semantic/mod.rs
+++ b/src/semantic/mod.rs
@@ -1,3 +1,6 @@
+use crate::ast_types::Expression;
+use crate::symbol_table::{_STRING, _BOOLEAN};
+
 use super::symbol_table::{SymbolTable, _NUMBER};
 use super::ast_types::{ModuleAST, Binding};
 
@@ -7,44 +10,49 @@ pub fn check_ast<'a>(ast: &'a mut ModuleAST, symbol_table: &'a mut SymbolTable)
         match binding {
             Binding::Val(val_binding) => {
                 // TODO: create a function to get the datatype, instead of a hardcoded value
-                symbol_table.add(val_binding.identifier, _NUMBER);
+                symbol_table.add(
+                    val_binding.identifier,
+                    get_expression_type(&val_binding.expression).as_str()
+                );
             }
             Binding::Var(var_binding) => {
                 // TODO: create a function to get the datatype, instead of a hardcoded value
-                symbol_table.add(var_binding.identifier, _NUMBER);
+                symbol_table.add(
+                    var_binding.identifier,
+                    get_expression_type(&var_binding.expression).as_str(),
+                );
             }
         }
     }
 }
 
+fn get_expression_type(exp: &Expression) -> String {
+    match exp {
+        Expression::Number(_) => String::from(_NUMBER),
+        Expression::String(_) => String::from(_STRING),
+        Expression::Boolean(_) => String::from(_BOOLEAN),
+    }
+}
+
 #[cfg(test)]
 mod tests {
+    use crate::symbol_table::_BOOLEAN;
+    use crate::symbol_table::_STRING;
     use crate::syntax;
     use crate::lexic;
 
     use super::*;
 
-    /*
-    val identifier = 20
+    fn test_type(input: String, datatype: &str) -> bool {
+        let tokens = lexic::get_tokens(&input).unwrap();
+        let mut table = SymbolTable::new();
+        let mut ast = syntax::construct_ast(&tokens).unwrap();
 
-    [Binding]
-    | identifier
-    | [Expression]
-      | [Number]
-        | 20
+        check_ast(&mut ast, &mut table);
 
-    - Check [Expression] is valid
-    - Check type of [Expression]
-    - Check if `identifier` already exists in the symbol table
-    - Create entry in symbol table
-
-    ->
-
-    SymbolTable {
-        identifier: Num
+        table.check_type("a", datatype)
     }
-     */
-
+    
     #[test]
     fn should_update_symbol_table() {
         let tokens = lexic::get_tokens(&String::from("val identifier = 20")).unwrap();
@@ -56,4 +64,16 @@ mod tests {
         let result = table.test("identifier");
         assert_eq!(true, result);
     }
+    
+    #[test]
+    fn should_get_correct_type() {
+        assert!(test_type(String::from("val a = 322"), _NUMBER));
+        assert!(test_type(String::from("var a = 322"), _NUMBER));
+        
+        assert!(test_type(String::from("val a = \"str\" "), _STRING));
+        assert!(test_type(String::from("var a = \"str\" "), _STRING));
+        
+        assert!(test_type(String::from("val a = false"), _BOOLEAN));
+        assert!(test_type(String::from("var a = true"), _BOOLEAN));
+    }
 }