diff --git a/benches/benchs.rs b/benches/benchs.rs
index 1832a22..beb32c3 100644
--- a/benches/benchs.rs
+++ b/benches/benchs.rs
@@ -1,16 +1,15 @@
 #![feature(test)]
+#![feature(bench_black_box)]
 
-extern crate test;
 extern crate rand;
 extern crate rand_pcg;
+extern crate test;
 
-use test::Bencher;
-use rand_pcg::Pcg32;
-use rand::{Rng, SeedableRng};
-use rand::distributions::Uniform;
-use rand::seq::SliceRandom;
 use evalexpr::build_operator_tree;
+use rand::{distributions::Uniform, seq::SliceRandom, Rng, SeedableRng};
+use rand_pcg::Pcg32;
 use std::hint::black_box;
+use test::Bencher;
 
 const BENCHMARK_LEN: usize = 100_000;
 const EXPONENTIAL_TUPLE_ITERATIONS: usize = 12;
@@ -69,9 +68,7 @@ fn bench_parse_long_expression_chains(bencher: &mut Bencher) {
     let mut gen = Pcg32::seed_from_u64(0);
     let long_expression_chain = generate_expression_chain(BENCHMARK_LEN, &mut gen);
 
-    bencher.iter(|| {
-        build_operator_tree(&long_expression_chain).unwrap()
-    });
+    bencher.iter(|| build_operator_tree(&long_expression_chain).unwrap());
 }
 
 #[bench]
@@ -79,9 +76,7 @@ fn bench_parse_deep_expression_trees(bencher: &mut Bencher) {
     let mut gen = Pcg32::seed_from_u64(15);
     let deep_expression_tree = generate_expression(BENCHMARK_LEN, &mut gen);
 
-    bencher.iter(|| {
-        build_operator_tree(&deep_expression_tree).unwrap()
-    });
+    bencher.iter(|| build_operator_tree(&deep_expression_tree).unwrap());
 }
 
 #[bench]
@@ -99,27 +94,28 @@ fn bench_parse_many_small_expressions(bencher: &mut Bencher) {
 #[bench]
 fn bench_evaluate_long_expression_chains(bencher: &mut Bencher) {
     let mut gen = Pcg32::seed_from_u64(0);
-    let long_expression_chain = build_operator_tree(&generate_expression_chain(BENCHMARK_LEN, &mut gen)).unwrap();
+    let long_expression_chain =
+        build_operator_tree(&generate_expression_chain(BENCHMARK_LEN, &mut gen)).unwrap();
 
-    bencher.iter(|| {
-        long_expression_chain.eval().unwrap()
-    });
+    bencher.iter(|| long_expression_chain.eval().unwrap());
 }
 
 #[bench]
 fn bench_evaluate_deep_expression_trees(bencher: &mut Bencher) {
     let mut gen = Pcg32::seed_from_u64(15);
-    let deep_expression_tree = build_operator_tree(&generate_expression(BENCHMARK_LEN, &mut gen)).unwrap();
+    let deep_expression_tree =
+        build_operator_tree(&generate_expression(BENCHMARK_LEN, &mut gen)).unwrap();
 
-    bencher.iter(|| {
-        deep_expression_tree.eval().unwrap()
-    });
+    bencher.iter(|| deep_expression_tree.eval().unwrap());
 }
 
 #[bench]
 fn bench_evaluate_many_small_expressions(bencher: &mut Bencher) {
     let mut gen = Pcg32::seed_from_u64(33);
-    let small_expressions: Vec<_> = generate_small_expressions(BENCHMARK_LEN, &mut gen).iter().map(|expression| build_operator_tree(&expression).unwrap()).collect();
+    let small_expressions: Vec<_> = generate_small_expressions(BENCHMARK_LEN, &mut gen)
+        .iter()
+        .map(|expression| build_operator_tree(&expression).unwrap())
+        .collect();
 
     bencher.iter(|| {
         for expression in &small_expressions {
@@ -131,10 +127,12 @@ fn bench_evaluate_many_small_expressions(bencher: &mut Bencher) {
 #[bench]
 fn bench_evaluate_large_tuple_expression(bencher: &mut Bencher) {
     let mut gen = Pcg32::seed_from_u64(44);
-    let large_tuple_expression = build_operator_tree(&generate_large_tuple_expression(EXPONENTIAL_TUPLE_ITERATIONS, &mut gen)).unwrap();
+    let large_tuple_expression = build_operator_tree(&generate_large_tuple_expression(
+        EXPONENTIAL_TUPLE_ITERATIONS,
+        &mut gen,
+    ))
+    .unwrap();
     dbg!(&large_tuple_expression);
 
-    bencher.iter(|| {
-        large_tuple_expression.eval().unwrap()
-    });
-}
\ No newline at end of file
+    bencher.iter(|| large_tuple_expression.eval().unwrap());
+}
diff --git a/rustfmt.toml b/rustfmt.toml
index e1b078b..bca1a3d 100644
--- a/rustfmt.toml
+++ b/rustfmt.toml
@@ -2,5 +2,5 @@ edition = "2018"
 reorder_imports=true
 reorder_modules=true
 format_strings=true
-merge_imports=true
+imports_granularity="Crate"
 match_block_trailing_comma=true
\ No newline at end of file
diff --git a/src/context/mod.rs b/src/context/mod.rs
index 7a062ac..0925cce 100644
--- a/src/context/mod.rs
+++ b/src/context/mod.rs
@@ -86,7 +86,7 @@ impl Context for HashMapContext {
     }
 
     fn set_function(&mut self, identifier: String, function: Function) -> EvalexprResult<()> {
-        self.functions.insert(identifier.into(), function);
+        self.functions.insert(identifier, function);
         Ok(())
     }
 }
diff --git a/src/function/builtin.rs b/src/function/builtin.rs
index a5f76c5..21f54fc 100644
--- a/src/function/builtin.rs
+++ b/src/function/builtin.rs
@@ -20,7 +20,7 @@ pub fn builtin_function(identifier: &str) -> Option<Function> {
                 } else if let Value::Int(int) = argument {
                     min_int = min_int.min(int);
                 } else {
-                    return Err(EvalexprError::expected_number(argument.clone()));
+                    return Err(EvalexprError::expected_number(argument));
                 }
             }
 
@@ -42,7 +42,7 @@ pub fn builtin_function(identifier: &str) -> Option<Function> {
                 } else if let Value::Int(int) = argument {
                     max_int = max_int.max(int);
                 } else {
-                    return Err(EvalexprError::expected_number(argument.clone()));
+                    return Err(EvalexprError::expected_number(argument));
                 }
             }
 
diff --git a/src/operator/mod.rs b/src/operator/mod.rs
index cc3aa01..e4cf713 100644
--- a/src/operator/mod.rs
+++ b/src/operator/mod.rs
@@ -136,21 +136,14 @@ impl Operator {
     // Make this a const fn once #57563 is resolved
     pub(crate) fn is_left_to_right(&self) -> bool {
         use crate::operator::Operator::*;
-        match self {
-            Assign => false,
-            FunctionIdentifier { identifier: _ } => false,
-            _ => true,
-        }
+        !matches!(self, Assign | FunctionIdentifier { identifier: _ })
     }
 
     /// Returns true if chains of this operator should be flattened into one operator with many arguments.
     // Make this a const fn once #57563 is resolved
     pub(crate) fn is_sequence(&self) -> bool {
         use crate::operator::Operator::*;
-        match self {
-            Tuple | Chain => true,
-            _ => false,
-        }
+        matches!(self, Tuple | Chain)
     }
 
     /// True if this operator is a leaf, meaning it accepts no arguments.
@@ -327,20 +320,12 @@ impl Operator {
             Eq => {
                 expect_operator_argument_amount(arguments.len(), 2)?;
 
-                if arguments[0] == arguments[1] {
-                    Ok(Value::Boolean(true))
-                } else {
-                    Ok(Value::Boolean(false))
-                }
+                Ok(Value::Boolean(arguments[0] == arguments[1]))
             },
             Neq => {
                 expect_operator_argument_amount(arguments.len(), 2)?;
 
-                if arguments[0] != arguments[1] {
-                    Ok(Value::Boolean(true))
-                } else {
-                    Ok(Value::Boolean(false))
-                }
+                Ok(Value::Boolean(arguments[0] != arguments[1]))
             },
             Gt => {
                 expect_operator_argument_amount(arguments.len(), 2)?;
@@ -348,23 +333,13 @@ impl Operator {
                 expect_number_or_string(&arguments[1])?;
 
                 if let (Ok(a), Ok(b)) = (arguments[0].as_string(), arguments[1].as_string()) {
-                    if a > b {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(a > b))
                 } else if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-                    if a > b {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(a > b))
                 } else {
-                    if arguments[0].as_number()? > arguments[1].as_number()? {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(
+                        arguments[0].as_number()? > arguments[1].as_number()?,
+                    ))
                 }
             },
             Lt => {
@@ -373,23 +348,13 @@ impl Operator {
                 expect_number_or_string(&arguments[1])?;
 
                 if let (Ok(a), Ok(b)) = (arguments[0].as_string(), arguments[1].as_string()) {
-                    if a < b {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(a < b))
                 } else if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-                    if a < b {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(a < b))
                 } else {
-                    if arguments[0].as_number()? < arguments[1].as_number()? {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(
+                        arguments[0].as_number()? < arguments[1].as_number()?,
+                    ))
                 }
             },
             Geq => {
@@ -398,23 +363,13 @@ impl Operator {
                 expect_number_or_string(&arguments[1])?;
 
                 if let (Ok(a), Ok(b)) = (arguments[0].as_string(), arguments[1].as_string()) {
-                    if a >= b {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(a >= b))
                 } else if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-                    if a >= b {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(a >= b))
                 } else {
-                    if arguments[0].as_number()? >= arguments[1].as_number()? {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(
+                        arguments[0].as_number()? >= arguments[1].as_number()?,
+                    ))
                 }
             },
             Leq => {
@@ -423,23 +378,13 @@ impl Operator {
                 expect_number_or_string(&arguments[1])?;
 
                 if let (Ok(a), Ok(b)) = (arguments[0].as_string(), arguments[1].as_string()) {
-                    if a <= b {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(a <= b))
                 } else if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-                    if a <= b {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(a <= b))
                 } else {
-                    if arguments[0].as_number()? <= arguments[1].as_number()? {
-                        Ok(Value::Boolean(true))
-                    } else {
-                        Ok(Value::Boolean(false))
-                    }
+                    Ok(Value::Boolean(
+                        arguments[0].as_number()? <= arguments[1].as_number()?,
+                    ))
                 }
             },
             And => {
@@ -447,32 +392,20 @@ impl Operator {
                 let a = arguments[0].as_boolean()?;
                 let b = arguments[1].as_boolean()?;
 
-                if a && b {
-                    Ok(Value::Boolean(true))
-                } else {
-                    Ok(Value::Boolean(false))
-                }
+                Ok(Value::Boolean(a && b))
             },
             Or => {
                 expect_operator_argument_amount(arguments.len(), 2)?;
                 let a = arguments[0].as_boolean()?;
                 let b = arguments[1].as_boolean()?;
 
-                if a || b {
-                    Ok(Value::Boolean(true))
-                } else {
-                    Ok(Value::Boolean(false))
-                }
+                Ok(Value::Boolean(a || b))
             },
             Not => {
                 expect_operator_argument_amount(arguments.len(), 1)?;
                 let a = arguments[0].as_boolean()?;
 
-                if !a {
-                    Ok(Value::Boolean(true))
-                } else {
-                    Ok(Value::Boolean(false))
-                }
+                Ok(Value::Boolean(!a))
             },
             Assign | AddAssign | SubAssign | MulAssign | DivAssign | ModAssign | ExpAssign
             | AndAssign | OrAssign => Err(EvalexprError::ContextNotManipulable),
@@ -528,7 +461,7 @@ impl Operator {
             Assign => {
                 expect_operator_argument_amount(arguments.len(), 2)?;
                 let target = arguments[0].as_string()?;
-                context.set_value(target.into(), arguments[1].clone())?;
+                context.set_value(target, arguments[1].clone())?;
 
                 Ok(Value::Empty)
             },
@@ -557,7 +490,7 @@ impl Operator {
                         self
                     ),
                 }?;
-                context.set_value(target.into(), result)?;
+                context.set_value(target, result)?;
 
                 Ok(Value::Empty)
             },
diff --git a/src/token/mod.rs b/src/token/mod.rs
index e33d34e..9da2c7b 100644
--- a/src/token/mod.rs
+++ b/src/token/mod.rs
@@ -196,11 +196,18 @@ impl Token {
 
     pub(crate) fn is_assignment(&self) -> bool {
         use Token::*;
-        match self {
-            Assign | PlusAssign | MinusAssign | StarAssign | SlashAssign | PercentAssign
-            | HatAssign | AndAssign | OrAssign => true,
-            _ => false,
-        }
+        matches!(
+            self,
+            Assign
+                | PlusAssign
+                | MinusAssign
+                | StarAssign
+                | SlashAssign
+                | PercentAssign
+                | HatAssign
+                | AndAssign
+                | OrAssign
+        )
     }
 }
 
@@ -210,7 +217,7 @@ fn parse_escape_sequence<Iter: Iterator<Item = char>>(iter: &mut Iter) -> Evalex
         Some('"') => Ok('"'),
         Some('\\') => Ok('\\'),
         Some(c) => Err(EvalexprError::IllegalEscapeSequence(format!("\\{}", c))),
-        None => Err(EvalexprError::IllegalEscapeSequence(format!("\\"))),
+        None => Err(EvalexprError::IllegalEscapeSequence("\\".to_string())),
     }
 }
 
@@ -268,7 +275,7 @@ fn str_to_partial_tokens(string: &str) -> EvalexprResult<Vec<PartialToken>> {
 /// Resolves all partial tokens by converting them to complex tokens.
 fn partial_tokens_to_tokens(mut tokens: &[PartialToken]) -> EvalexprResult<Vec<Token>> {
     let mut result = Vec::new();
-    while tokens.len() > 0 {
+    while !tokens.is_empty() {
         let first = tokens[0].clone();
         let second = tokens.get(1).cloned();
         let third = tokens.get(2).cloned();
diff --git a/src/tree/mod.rs b/src/tree/mod.rs
index 9d7a78d..7cca5d7 100644
--- a/src/tree/mod.rs
+++ b/src/tree/mod.rs
@@ -1,4 +1,8 @@
-use crate::{token::Token, value::{TupleType, EMPTY_VALUE}, EmptyType, FloatType, IntType, HashMapContext};
+use crate::{
+    token::Token,
+    value::{TupleType, EMPTY_VALUE},
+    EmptyType, FloatType, HashMapContext, IntType,
+};
 
 use crate::{
     context::Context,
@@ -28,7 +32,7 @@ mod iter;
 /// assert_eq!(node.eval_with_context(&context), Ok(Value::from(3)));
 /// ```
 ///
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Clone)]
 pub struct Node {
     operator: Operator,
     children: Vec<Node>,
diff --git a/src/value/mod.rs b/src/value/mod.rs
index 976664e..b5b14a4 100644
--- a/src/value/mod.rs
+++ b/src/value/mod.rs
@@ -40,57 +40,36 @@ pub enum Value {
 impl Value {
     /// Returns true if `self` is a `Value::String`.
     pub fn is_string(&self) -> bool {
-        match self {
-            Value::String(_) => true,
-            _ => false,
-        }
+        matches!(self, Value::String(_))
     }
     /// Returns true if `self` is a `Value::Int`.
     pub fn is_int(&self) -> bool {
-        match self {
-            Value::Int(_) => true,
-            _ => false,
-        }
+        matches!(self, Value::Int(_))
     }
 
     /// Returns true if `self` is a `Value::Float`.
     pub fn is_float(&self) -> bool {
-        match self {
-            Value::Float(_) => true,
-            _ => false,
-        }
+        matches!(self, Value::Float(_))
     }
 
     /// Returns true if `self` is a `Value::Int` or `Value::Float`.
     pub fn is_number(&self) -> bool {
-        match self {
-            Value::Int(_) | Value::Float(_) => true,
-            _ => false,
-        }
+        matches!(self, Value::Int(_) | Value::Float(_))
     }
 
     /// Returns true if `self` is a `Value::Boolean`.
     pub fn is_boolean(&self) -> bool {
-        match self {
-            Value::Boolean(_) => true,
-            _ => false,
-        }
+        matches!(self, Value::Boolean(_))
     }
 
     /// Returns true if `self` is a `Value::Tuple`.
     pub fn is_tuple(&self) -> bool {
-        match self {
-            Value::Tuple(_) => true,
-            _ => false,
-        }
+        matches!(self, Value::Tuple(_))
     }
 
     /// Returns true if `self` is a `Value::Empty`.
     pub fn is_empty(&self) -> bool {
-        match self {
-            Value::Empty => true,
-            _ => false,
-        }
+        matches!(self, Value::Empty)
     }
 
     /// Clones the value stored in `self` as `String`, or returns `Err` if `self` is not a `Value::String`.
diff --git a/tests/integration.rs b/tests/integration.rs
index 7957c9b..6c3dddc 100644
--- a/tests/integration.rs
+++ b/tests/integration.rs
@@ -452,7 +452,6 @@ fn test_shortcut_functions() {
             .eval_string_with_context_mut(&mut context),
         Ok("a string".to_string())
     );
-    ;
     assert_eq!(
         build_operator_tree("3.3")
             .unwrap()