diff --git a/Cargo.lock b/Cargo.lock
index 58ab771..fe3023d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -92,7 +92,7 @@ dependencies = [
 
 [[package]]
 name = "thp"
-version = "0.1.0"
+version = "0.1.1"
 dependencies = [
  "colored",
  "serde",
diff --git a/Cargo.toml b/Cargo.toml
index 31aec6d..4f0095f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "thp"
-version = "0.1.0"
+version = "0.1.1"
 edition = "2021"
 
 
diff --git a/src/semantic/checks/function_declaration.rs b/src/semantic/checks/function_declaration.rs
index f05a6db..ccb877b 100644
--- a/src/semantic/checks/function_declaration.rs
+++ b/src/semantic/checks/function_declaration.rs
@@ -37,14 +37,24 @@ impl SemanticCheck for FunctionDeclaration<'_> {
                         return Err(err);
                     }
                 }
-                BlockMember::Stmt(Statement::FnDecl(_)) => {
-                    todo!("Function declaration: semantic check not implemented")
+                BlockMember::Stmt(Statement::FnDecl(f)) => {
+                    // TODO: (for now) a function cannot be declared inside another function.
+                    let error = SemanticError {
+                        error_start: f.identifier.position,
+                        error_end: f.identifier.get_end_position(),
+                        reason: format!(
+                            "A function cannot be defined inside another function."
+                        ),
+                    };
+
+                    return Err(MistiError::Semantic(error));
                 }
-                _ => todo!("Expression: semantic check not implemented"),
+                BlockMember::Expr(e) => e.check_semantics(scope)?,
             }
         }
 
-        // TODO: Check the return type of the function
+        // TODO: Check that the return type of the function
+        // matches the return type of the last expression
 
         scope.insert(function_name, Type::Function(vec![], "Unit".into()));