diff --git a/dust-lang/src/abstract_tree/built_in_function.rs b/dust-lang/src/abstract_tree/built_in_function.rs
index 4616c41..7a156d6 100644
--- a/dust-lang/src/abstract_tree/built_in_function.rs
+++ b/dust-lang/src/abstract_tree/built_in_function.rs
@@ -71,7 +71,7 @@ impl FunctionLogic for Length {
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
+    fn call(context: &Context, _: bool) -> Result<Option<Value>, RuntimeError> {
         let value = if let Some(value) = context.get_value(&Identifier::new("input"))? {
             value
         } else {
@@ -103,7 +103,7 @@ impl FunctionLogic for ReadFile {
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
+    fn call(context: &Context, _: bool) -> Result<Option<Value>, RuntimeError> {
         let value = if let Some(value) = context.get_value(&Identifier::new("path"))? {
             value
         } else {
@@ -136,12 +136,12 @@ impl FunctionLogic for ReadLine {
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
+    fn call(_: &Context, _: bool) -> Result<Option<Value>, RuntimeError> {
         let mut user_input = String::new();
 
         stdin().read_line(&mut user_input)?;
 
-        Ok(Some(Value::string(user_input)))
+        Ok(Some(Value::string(user_input.trim_end_matches('\n'))))
     }
 }
 
@@ -157,7 +157,7 @@ impl FunctionLogic for Sleep {
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
+    fn call(context: &Context, _: bool) -> Result<Option<Value>, RuntimeError> {
         let value = if let Some(value) = context.get_value(&Identifier::new("milliseconds"))? {
             value
         } else {
@@ -191,7 +191,7 @@ impl FunctionLogic for WriteLine {
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
+    fn call(context: &Context, _: bool) -> Result<Option<Value>, RuntimeError> {
         let value = if let Some(value) = context.get_value(&Identifier::new("output"))? {
             value
         } else {
@@ -230,7 +230,7 @@ impl FunctionLogic for JsonParse {
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
+    fn call(context: &Context, _: bool) -> Result<Option<Value>, RuntimeError> {
         let target_type = if let Some(r#type) = context.get_type(&Identifier::new("T"))? {
             r#type
         } else {
diff --git a/dust-lang/src/abstract_tree/function_call.rs b/dust-lang/src/abstract_tree/function_call.rs
index ec9a419..d7751cd 100644
--- a/dust-lang/src/abstract_tree/function_call.rs
+++ b/dust-lang/src/abstract_tree/function_call.rs
@@ -1,4 +1,3 @@
-use chumsky::container::Container;
 use serde::{Deserialize, Serialize};
 
 use crate::{
@@ -56,19 +55,14 @@ impl AbstractNode for FunctionCall {
             }
         }
 
-        let function_node_type = if let Expression::Value(WithPosition {
-            node: ValueNode::BuiltInFunction(function),
-            ..
-        }) = self.function_expression.as_ref()
-        {
-            function.r#type()
-        } else if let Some(r#type) = self.function_expression.expected_type(context)? {
-            r#type
-        } else {
-            return Err(ValidationError::ExpectedExpression(
-                self.function_expression.position(),
-            ));
-        };
+        let function_node_type =
+            if let Some(r#type) = self.function_expression.expected_type(context)? {
+                r#type
+            } else {
+                return Err(ValidationError::ExpectedExpression(
+                    self.function_expression.position(),
+                ));
+            };
 
         if let Type::Function {
             type_parameters,
diff --git a/dust-lang/src/abstract_tree/type.rs b/dust-lang/src/abstract_tree/type.rs
index 04b76bc..c39c75c 100644
--- a/dust-lang/src/abstract_tree/type.rs
+++ b/dust-lang/src/abstract_tree/type.rs
@@ -264,7 +264,7 @@ impl Display for Type {
                 value_parameters,
                 return_type,
             } => {
-                write!(f, "(")?;
+                write!(f, "fn (")?;
 
                 if let Some(type_parameters) = type_parameters {
                     for identifier in type_parameters {
diff --git a/dust-lang/src/identifier.rs b/dust-lang/src/identifier.rs
index ac8999f..9362c20 100644
--- a/dust-lang/src/identifier.rs
+++ b/dust-lang/src/identifier.rs
@@ -16,19 +16,19 @@ fn identifier_cache<'a>() -> &'a RwLock<HashMap<String, Identifier>> {
 pub struct Identifier(Arc<String>);
 
 impl Identifier {
-    pub fn new(string: &str) -> Self {
+    pub fn new(text: &str) -> Self {
         let cache = identifier_cache();
 
-        if let Some(identifier) = cache.read().unwrap().get(string) {
+        if let Some(identifier) = cache.read().unwrap().get(text) {
             return identifier.clone();
         }
 
-        let identifier = Identifier(Arc::new(string.to_string()));
+        let identifier = Identifier(Arc::new(text.to_string()));
 
         cache
             .write()
             .unwrap()
-            .insert(string.to_string(), identifier.clone());
+            .insert(text.to_string(), identifier.clone());
 
         identifier
     }