diff --git a/src/context/mod.rs b/src/context/mod.rs
index 568f7e2..b2ce29f 100644
--- a/src/context/mod.rs
+++ b/src/context/mod.rs
@@ -26,10 +26,18 @@ pub trait Context {
 /// The HashMapContext is type-safe and returns an error if the user tries to assign a value of a different type than before to an identifier.
 pub trait ContextMut: Context {
     /// Links the given value to the given identifier.
-    fn set_value<S: Into<String>, V: Into<Value>>(&mut self, identifier: S, value: V) -> EvalexprResult<()>;
+    fn set_value<S: Into<String>, V: Into<Value>>(
+        &mut self,
+        identifier: S,
+        value: V,
+    ) -> EvalexprResult<()>;
 
     /// Links the given function to the given identifier.
-    fn set_function<S: Into<String>>(&mut self, identifier: S, function: Function) -> EvalexprResult<()>;
+    fn set_function<S: Into<String>>(
+        &mut self,
+        identifier: S,
+        function: Function,
+    ) -> EvalexprResult<()>;
 }
 
 /// A context that returns `None` for each identifier.
@@ -46,11 +54,19 @@ impl Context for EmptyContext {
 }
 
 impl ContextMut for EmptyContext {
-    fn set_value<S: Into<String>, V: Into<Value>>(&mut self, _identifier: S, _value: V) -> EvalexprResult<()> {
+    fn set_value<S: Into<String>, V: Into<Value>>(
+        &mut self,
+        _identifier: S,
+        _value: V,
+    ) -> EvalexprResult<()> {
         Err(EvalexprError::ContextNotManipulable)
     }
 
-    fn set_function<S: Into<String>>(&mut self, _identifier: S, _function: Function) -> EvalexprResult<()> {
+    fn set_function<S: Into<String>>(
+        &mut self,
+        _identifier: S,
+        _function: Function,
+    ) -> EvalexprResult<()> {
         Err(EvalexprError::ContextNotManipulable)
     }
 }
@@ -86,7 +102,11 @@ impl Context for HashMapContext {
 }
 
 impl ContextMut for HashMapContext {
-    fn set_value<S: Into<String>, V: Into<Value>>(&mut self, identifier: S, value: V) -> Result<(), EvalexprError> {
+    fn set_value<S: Into<String>, V: Into<Value>>(
+        &mut self,
+        identifier: S,
+        value: V,
+    ) -> Result<(), EvalexprError> {
         let identifier = identifier.into();
         let value = value.into();
         if let Some(existing_value) = self.variables.get_mut(&identifier) {
@@ -103,8 +123,12 @@ impl ContextMut for HashMapContext {
         Ok(())
     }
 
-    fn set_function<S: Into<String>>(&mut self, identifier: S, function: Function) -> Result<(), EvalexprError> {
+    fn set_function<S: Into<String>>(
+        &mut self,
+        identifier: S,
+        function: Function,
+    ) -> Result<(), EvalexprError> {
         self.functions.insert(identifier.into(), function);
         Ok(())
     }
-}
\ No newline at end of file
+}
diff --git a/src/error/mod.rs b/src/error/mod.rs
index 08c2359..07cac90 100644
--- a/src/error/mod.rs
+++ b/src/error/mod.rs
@@ -6,8 +6,7 @@
 //! They are meant as shortcuts to not write the same error checking code everywhere.
 
 use token::PartialToken;
-use value::TupleType;
-use value::value_type::ValueType;
+use value::{TupleType, value_type::ValueType};
 
 use crate::value::Value;
 
diff --git a/src/interface/mod.rs b/src/interface/mod.rs
index 2b404fc..afd7725 100644
--- a/src/interface/mod.rs
+++ b/src/interface/mod.rs
@@ -39,10 +39,7 @@ pub fn eval(string: &str) -> Result<Value, EvalexprError> {
 /// ```
 ///
 /// *See the [crate doc](index.html) for more examples and explanations of the expression format.*
-pub fn eval_with_context(
-    string: &str,
-    context: &Context,
-) -> Result<Value, EvalexprError> {
+pub fn eval_with_context(string: &str, context: &Context) -> Result<Value, EvalexprError> {
     tree::tokens_to_operator_tree(token::tokenize(string)?)?.eval_with_context(context)
 }
 
@@ -132,10 +129,7 @@ pub fn eval_tuple(string: &str) -> Result<TupleType, EvalexprError> {
 /// Evaluate the given expression string into a string with the given context.
 ///
 /// *See the [crate doc](index.html) for more examples and explanations of the expression format.*
-pub fn eval_string_with_context(
-    string: &str,
-    context: &Context,
-) -> Result<String, EvalexprError> {
+pub fn eval_string_with_context(string: &str, context: &Context) -> Result<String, EvalexprError> {
     match eval_with_context(string, context) {
         Ok(Value::String(string)) => Ok(string),
         Ok(value) => Err(EvalexprError::expected_string(value)),
@@ -146,10 +140,7 @@ pub fn eval_string_with_context(
 /// Evaluate the given expression string into an integer with the given context.
 ///
 /// *See the [crate doc](index.html) for more examples and explanations of the expression format.*
-pub fn eval_int_with_context(
-    string: &str,
-    context: &Context,
-) -> Result<IntType, EvalexprError> {
+pub fn eval_int_with_context(string: &str, context: &Context) -> Result<IntType, EvalexprError> {
     match eval_with_context(string, context) {
         Ok(Value::Int(int)) => Ok(int),
         Ok(value) => Err(EvalexprError::expected_int(value)),
@@ -174,10 +165,7 @@ pub fn eval_float_with_context(
 /// Evaluate the given expression string into a boolean with the given context.
 ///
 /// *See the [crate doc](index.html) for more examples and explanations of the expression format.*
-pub fn eval_boolean_with_context(
-    string: &str,
-    context: &Context,
-) -> Result<bool, EvalexprError> {
+pub fn eval_boolean_with_context(string: &str, context: &Context) -> Result<bool, EvalexprError> {
     match eval_with_context(string, context) {
         Ok(Value::Boolean(boolean)) => Ok(boolean),
         Ok(value) => Err(EvalexprError::expected_boolean(value)),
diff --git a/src/operator/mod.rs b/src/operator/mod.rs
index 9d97a5c..f803679 100644
--- a/src/operator/mod.rs
+++ b/src/operator/mod.rs
@@ -29,11 +29,7 @@ pub trait Operator: Debug + Display {
     fn argument_amount(&self) -> usize;
 
     /// Evaluates the operator with the given arguments and context.
-    fn eval(
-        &self,
-        arguments: &[Value],
-        context: &Context,
-    ) -> Result<Value, EvalexprError>;
+    fn eval(&self, arguments: &[Value], context: &Context) -> Result<Value, EvalexprError>;
 }
 
 #[derive(Debug)]
@@ -122,11 +118,7 @@ impl Operator for RootNode {
         1
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 1)?;
         Ok(arguments[0].clone())
     }
@@ -145,11 +137,7 @@ impl Operator for Add {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -185,11 +173,7 @@ impl Operator for Sub {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -225,11 +209,7 @@ impl Operator for Neg {
         1
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 1)?;
         expect_number(&arguments[0])?;
 
@@ -259,11 +239,7 @@ impl Operator for Mul {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -299,11 +275,7 @@ impl Operator for Div {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -339,11 +311,7 @@ impl Operator for Mod {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -379,11 +347,7 @@ impl Operator for Exp {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -410,11 +374,7 @@ impl Operator for Eq {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
 
         if arguments[0] == arguments[1] {
@@ -438,11 +398,7 @@ impl Operator for Neq {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
 
         if arguments[0] != arguments[1] {
@@ -466,11 +422,7 @@ impl Operator for Gt {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -504,11 +456,7 @@ impl Operator for Lt {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -542,11 +490,7 @@ impl Operator for Geq {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -580,11 +524,7 @@ impl Operator for Leq {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
@@ -618,11 +558,7 @@ impl Operator for And {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         let a = expect_boolean(&arguments[0])?;
         let b = expect_boolean(&arguments[1])?;
@@ -648,11 +584,7 @@ impl Operator for Or {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 2)?;
         let a = expect_boolean(&arguments[0])?;
         let b = expect_boolean(&arguments[1])?;
@@ -678,11 +610,7 @@ impl Operator for Not {
         1
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 1)?;
         let a = expect_boolean(&arguments[0])?;
 
@@ -707,11 +635,7 @@ impl Operator for Tuple {
         2
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         if let Value::Tuple(tuple) = &arguments[0] {
             let mut tuple = tuple.clone();
             if let Value::Tuple(tuple2) = &arguments[1] {
@@ -748,11 +672,7 @@ impl Operator for Const {
         0
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        _context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], _context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 0)?;
 
         Ok(self.value.clone())
@@ -772,11 +692,7 @@ impl Operator for VariableIdentifier {
         0
     }
 
-    fn eval(
-        &self,
-        _arguments: &[Value],
-        context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, _arguments: &[Value], context: &Context) -> Result<Value, EvalexprError> {
         if let Some(value) = context.get_value(&self.identifier).cloned() {
             Ok(value)
         } else {
@@ -800,11 +716,7 @@ impl Operator for FunctionIdentifier {
         1
     }
 
-    fn eval(
-        &self,
-        arguments: &[Value],
-        context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    fn eval(&self, arguments: &[Value], context: &Context) -> Result<Value, EvalexprError> {
         expect_operator_argument_amount(arguments.len(), 1)?;
 
         let arguments = if let Value::Tuple(arguments) = &arguments[0] {
diff --git a/src/tree/mod.rs b/src/tree/mod.rs
index 6551dc7..f967fed 100644
--- a/src/tree/mod.rs
+++ b/src/tree/mod.rs
@@ -46,10 +46,7 @@ impl Node {
     /// Evaluates the operator tree rooted at this node with the given context.
     ///
     /// Fails, if one of the operators in the expression tree fails.
-    pub fn eval_with_context(
-        &self,
-        context: &Context,
-    ) -> Result<Value, EvalexprError> {
+    pub fn eval_with_context(&self, context: &Context) -> Result<Value, EvalexprError> {
         let mut arguments = Vec::new();
         for child in self.children() {
             arguments.push(child.eval_with_context(context)?);
@@ -67,10 +64,7 @@ impl Node {
     /// Evaluates the operator tree rooted at this node into a string with an the given context.
     ///
     /// Fails, if one of the operators in the expression tree fails.
-    pub fn eval_string_with_context(
-        &self,
-        context: &Context,
-    ) -> Result<String, EvalexprError> {
+    pub fn eval_string_with_context(&self, context: &Context) -> Result<String, EvalexprError> {
         match self.eval_with_context(context) {
             Ok(Value::String(string)) => Ok(string),
             Ok(value) => Err(EvalexprError::expected_string(value)),
@@ -81,10 +75,7 @@ impl Node {
     /// Evaluates the operator tree rooted at this node into a float with an the given context.
     ///
     /// Fails, if one of the operators in the expression tree fails.
-    pub fn eval_float_with_context(
-        &self,
-        context: &Context,
-    ) -> Result<FloatType, EvalexprError> {
+    pub fn eval_float_with_context(&self, context: &Context) -> Result<FloatType, EvalexprError> {
         match self.eval_with_context(context) {
             Ok(Value::Float(float)) => Ok(float),
             Ok(value) => Err(EvalexprError::expected_float(value)),
@@ -95,10 +86,7 @@ impl Node {
     /// Evaluates the operator tree rooted at this node into an integer with an the given context.
     ///
     /// Fails, if one of the operators in the expression tree fails.
-    pub fn eval_int_with_context(
-        &self,
-        context: &Context,
-    ) -> Result<IntType, EvalexprError> {
+    pub fn eval_int_with_context(&self, context: &Context) -> Result<IntType, EvalexprError> {
         match self.eval_with_context(context) {
             Ok(Value::Int(int)) => Ok(int),
             Ok(value) => Err(EvalexprError::expected_int(value)),
@@ -109,10 +97,7 @@ impl Node {
     /// Evaluates the operator tree rooted at this node into a boolean with an the given context.
     ///
     /// Fails, if one of the operators in the expression tree fails.
-    pub fn eval_boolean_with_context(
-        &self,
-        context: &Context,
-    ) -> Result<bool, EvalexprError> {
+    pub fn eval_boolean_with_context(&self, context: &Context) -> Result<bool, EvalexprError> {
         match self.eval_with_context(context) {
             Ok(Value::Boolean(boolean)) => Ok(boolean),
             Ok(value) => Err(EvalexprError::expected_boolean(value)),
@@ -123,10 +108,7 @@ impl Node {
     /// Evaluates the operator tree rooted at this node into a tuple with an the given context.
     ///
     /// Fails, if one of the operators in the expression tree fails.
-    pub fn eval_tuple_with_context(
-        &self,
-        context: &Context,
-    ) -> Result<TupleType, EvalexprError> {
+    pub fn eval_tuple_with_context(&self, context: &Context) -> Result<TupleType, EvalexprError> {
         match self.eval_with_context(context) {
             Ok(Value::Tuple(tuple)) => Ok(tuple),
             Ok(value) => Err(EvalexprError::expected_tuple(value)),
diff --git a/src/value/value_type.rs b/src/value/value_type.rs
index 360bf08..8c5081c 100644
--- a/src/value/value_type.rs
+++ b/src/value/value_type.rs
@@ -37,4 +37,4 @@ impl From<&&mut Value> for ValueType {
     fn from(value: &&mut Value) -> Self {
         From::<&Value>::from(*value)
     }
-}
\ No newline at end of file
+}
diff --git a/tests/integration.rs b/tests/integration.rs
index f99373f..0490b3b 100644
--- a/tests/integration.rs
+++ b/tests/integration.rs
@@ -107,14 +107,8 @@ fn test_with_context() {
     context.set_value("half", Value::Float(0.5)).unwrap();
     context.set_value("zero", Value::Int(0)).unwrap();
 
-    assert_eq!(
-        eval_with_context("tr", &context),
-        Ok(Value::Boolean(true))
-    );
-    assert_eq!(
-        eval_with_context("fa", &context),
-        Ok(Value::Boolean(false))
-    );
+    assert_eq!(eval_with_context("tr", &context), Ok(Value::Boolean(true)));
+    assert_eq!(eval_with_context("fa", &context), Ok(Value::Boolean(false)));
     assert_eq!(
         eval_with_context("tr && false", &context),
         Ok(Value::Boolean(false))
@@ -136,39 +130,31 @@ fn test_with_context() {
 #[test]
 fn test_functions() {
     let mut context = HashMapContext::new();
-    context.set_function(
-        "sub2".to_string(),
-        Function::new(
-            Some(1),
-            Box::new(|arguments| {
-                if let Value::Int(int) = arguments[0] {
-                    Ok(Value::Int(int - 2))
-                } else if let Value::Float(float) = arguments[0] {
-                    Ok(Value::Float(float - 2.0))
-                } else {
-                    Err(EvalexprError::expected_number(arguments[0].clone()))
-                }
-            }),
-        ),
-    ).unwrap();
-    context.set_value("five".to_string(), Value::Int(5)).unwrap();
+    context
+        .set_function(
+            "sub2".to_string(),
+            Function::new(
+                Some(1),
+                Box::new(|arguments| {
+                    if let Value::Int(int) = arguments[0] {
+                        Ok(Value::Int(int - 2))
+                    } else if let Value::Float(float) = arguments[0] {
+                        Ok(Value::Float(float - 2.0))
+                    } else {
+                        Err(EvalexprError::expected_number(arguments[0].clone()))
+                    }
+                }),
+            ),
+        )
+        .unwrap();
+    context
+        .set_value("five".to_string(), Value::Int(5))
+        .unwrap();
 
-    assert_eq!(
-        eval_with_context("sub2 5", &context),
-        Ok(Value::Int(3))
-    );
-    assert_eq!(
-        eval_with_context("sub2(5)", &context),
-        Ok(Value::Int(3))
-    );
-    assert_eq!(
-        eval_with_context("sub2 five", &context),
-        Ok(Value::Int(3))
-    );
-    assert_eq!(
-        eval_with_context("sub2(five)", &context),
-        Ok(Value::Int(3))
-    );
+    assert_eq!(eval_with_context("sub2 5", &context), Ok(Value::Int(3)));
+    assert_eq!(eval_with_context("sub2(5)", &context), Ok(Value::Int(3)));
+    assert_eq!(eval_with_context("sub2 five", &context), Ok(Value::Int(3)));
+    assert_eq!(eval_with_context("sub2(five)", &context), Ok(Value::Int(3)));
     assert_eq!(
         eval_with_context("sub2(3) + five", &context),
         Ok(Value::Int(6))
@@ -178,74 +164,81 @@ fn test_functions() {
 #[test]
 fn test_n_ary_functions() {
     let mut context = HashMapContext::new();
-    context.set_function(
-        "sub2",
-        Function::new(
-            Some(1),
-            Box::new(|arguments| {
-                if let Value::Int(int) = arguments[0] {
-                    Ok(Value::Int(int - 2))
-                } else if let Value::Float(float) = arguments[0] {
-                    Ok(Value::Float(float - 2.0))
-                } else {
-                    Err(EvalexprError::expected_number(arguments[0].clone()))
-                }
-            }),
-        ),
-    ).unwrap();
-    context.set_function(
-        "avg",
-        Function::new(
-            Some(2),
-            Box::new(|arguments| {
-                expect_number(&arguments[0])?;
-                expect_number(&arguments[1])?;
+    context
+        .set_function(
+            "sub2",
+            Function::new(
+                Some(1),
+                Box::new(|arguments| {
+                    if let Value::Int(int) = arguments[0] {
+                        Ok(Value::Int(int - 2))
+                    } else if let Value::Float(float) = arguments[0] {
+                        Ok(Value::Float(float - 2.0))
+                    } else {
+                        Err(EvalexprError::expected_number(arguments[0].clone()))
+                    }
+                }),
+            ),
+        )
+        .unwrap();
+    context
+        .set_function(
+            "avg",
+            Function::new(
+                Some(2),
+                Box::new(|arguments| {
+                    expect_number(&arguments[0])?;
+                    expect_number(&arguments[1])?;
 
-                if let (Value::Int(a), Value::Int(b)) = (&arguments[0], &arguments[1]) {
-                    Ok(Value::Int((a + b) / 2))
-                } else {
-                    Ok(Value::Float(
-                        (arguments[0].as_float()? + arguments[1].as_float()?) / 2.0,
-                    ))
-                }
-            }),
-        ),
-    ).unwrap();
-    context.set_function(
-        "muladd",
-        Function::new(
-            Some(3),
-            Box::new(|arguments| {
-                expect_number(&arguments[0])?;
-                expect_number(&arguments[1])?;
-                expect_number(&arguments[2])?;
+                    if let (Value::Int(a), Value::Int(b)) = (&arguments[0], &arguments[1]) {
+                        Ok(Value::Int((a + b) / 2))
+                    } else {
+                        Ok(Value::Float(
+                            (arguments[0].as_float()? + arguments[1].as_float()?) / 2.0,
+                        ))
+                    }
+                }),
+            ),
+        )
+        .unwrap();
+    context
+        .set_function(
+            "muladd",
+            Function::new(
+                Some(3),
+                Box::new(|arguments| {
+                    expect_number(&arguments[0])?;
+                    expect_number(&arguments[1])?;
+                    expect_number(&arguments[2])?;
 
-                if let (Value::Int(a), Value::Int(b), Value::Int(c)) =
+                    if let (Value::Int(a), Value::Int(b), Value::Int(c)) =
                     (&arguments[0], &arguments[1], &arguments[2])
-                {
-                    Ok(Value::Int(a * b + c))
-                } else {
-                    Ok(Value::Float(
-                        arguments[0].as_float()? * arguments[1].as_float()?
-                            + arguments[2].as_float()?,
-                    ))
-                }
-            }),
-        ),
-    ).unwrap();
-    context.set_function(
-        "count",
-        Function::new(
-            None,
-            Box::new(|arguments| Ok(Value::Int(arguments.len() as IntType))),
-        ),
-    ).unwrap();
-    context.set_value("five".to_string(), Value::Int(5)).unwrap();
+                    {
+                        Ok(Value::Int(a * b + c))
+                    } else {
+                        Ok(Value::Float(
+                            arguments[0].as_float()? * arguments[1].as_float()?
+                                + arguments[2].as_float()?,
+                        ))
+                    }
+                }),
+            ),
+        )
+        .unwrap();
+    context
+        .set_function(
+            "count",
+            Function::new(
+                None,
+                Box::new(|arguments| Ok(Value::Int(arguments.len() as IntType))),
+            ),
+        )
+        .unwrap();
+    context
+        .set_value("five".to_string(), Value::Int(5))
+        .unwrap();
 
-    assert_eq!(
-        eval_with_context("avg(7, 5)", &context),
-        Ok(Value::Int(6))
-    );
+    assert_eq!(eval_with_context("avg(7, 5)", &context), Ok(Value::Int(6)));
     assert_eq!(
         eval_with_context("avg(sub2 5, 5)", &context),
         Ok(Value::Int(4))
@@ -273,10 +266,7 @@ fn test_n_ary_functions() {
         eval_with_context("count(3, 5.5, 2)", &context),
         Ok(Value::Int(3))
     );
-    assert_eq!(
-        eval_with_context("count 5", &context),
-        Ok(Value::Int(1))
-    );
+    assert_eq!(eval_with_context("count 5", &context), Ok(Value::Int(1)));
 
     assert_eq!(
         eval_with_context("min(4.0, 3)", &context),
@@ -342,7 +332,9 @@ fn test_no_panic() {
 #[test]
 fn test_shortcut_functions() {
     let mut context = HashMapContext::new();
-    context.set_value("string", Value::from("a string")).unwrap();
+    context
+        .set_value("string", Value::from("a string"))
+        .unwrap();
 
     // assert_eq!(eval_string("???"));
     assert_eq!(
@@ -350,17 +342,11 @@ fn test_shortcut_functions() {
         Ok("a string".to_string())
     );
     assert_eq!(eval_float("3.3"), Ok(3.3));
-    assert_eq!(
-        eval_float_with_context("3.3", &context),
-        Ok(3.3)
-    );
+    assert_eq!(eval_float_with_context("3.3", &context), Ok(3.3));
     assert_eq!(eval_int("3"), Ok(3));
     assert_eq!(eval_int_with_context("3", &context), Ok(3));
     assert_eq!(eval_boolean("true"), Ok(true));
-    assert_eq!(
-        eval_boolean_with_context("true", &context),
-        Ok(true)
-    );
+    assert_eq!(eval_boolean_with_context("true", &context), Ok(true));
     assert_eq!(eval_tuple("3,3"), Ok(vec![Value::Int(3), Value::Int(3)]));
     assert_eq!(
         eval_tuple_with_context("3,3", &context),