Get rid of some unwraps

Relates to #14

src/interface/mod.rs

@@ -1,13 +1,13 @@
-use token;
-use tree;
-use value::TupleType;
 use Configuration;
 use EmptyConfiguration;
 use Error;
 use FloatType;
 use IntType;
 use Node;
+use token;
+use tree;
 use Value;
+use value::TupleType;
 
 /// Evaluate the given expression string.
 ///
@@ -56,7 +56,7 @@ pub fn eval_with_configuration(
 /// ```rust
 /// use evalexpr::*;
 ///
-/// let precomputed = build_operator_tree("one + two + three").unwrap();
+/// let precomputed = build_operator_tree("one + two + three").unwrap(); // Do proper error handling here
 ///
 /// let mut configuration = HashMapConfiguration::new();
 /// configuration.insert_variable("one", 1);

src/lib.rs

@@ -71,7 +71,7 @@
 //! ```rust
 //! use evalexpr::*;
 //!
-//! let precompiled = build_operator_tree("a * b - c > 5").unwrap();
+//! let precompiled = build_operator_tree("a * b - c > 5").unwrap(); // Do proper error handling here
 //!
 //! let mut configuration = HashMapConfiguration::new();
 //! configuration.insert_variable("a", 6);
@@ -269,6 +269,13 @@ extern crate ron;
 #[cfg(feature = "serde")]
 extern crate serde;
 
+pub use configuration::{Configuration, EmptyConfiguration, HashMapConfiguration};
+pub use error::Error;
+pub use function::Function;
+pub use interface::*;
+pub use tree::Node;
+pub use value::{FloatType, IntType, Value};
+
 mod configuration;
 pub mod error;
 #[cfg(feature = "serde")]
@@ -282,9 +289,3 @@ mod value;
 
 // Exports
 
-pub use configuration::{Configuration, EmptyConfiguration, HashMapConfiguration};
-pub use error::Error;
-pub use function::Function;
-pub use interface::*;
-pub use tree::Node;
-pub use value::{FloatType, IntType, Value};

src/operator/mod.rs

@@ -1,7 +1,9 @@
-use crate::{configuration::Configuration, error::*, value::Value};
-use function::builtin::builtin_function;
 use std::fmt::{Debug, Display};
 
+use function::builtin::builtin_function;
+
+use crate::{configuration::Configuration, error::*, value::Value};
+
 mod display;
 
 pub trait Operator: Debug + Display {
@@ -140,11 +142,8 @@ impl Operator for Add {
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
 
-        if arguments[0].is_int() && arguments[1].is_int() {
+        if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-            let result = arguments[0]
+            let result = a.checked_add(b);
-                .as_int()
-                .unwrap()
-                .checked_add(arguments[1].as_int().unwrap());
             if let Some(result) = result {
                 Ok(Value::Int(result))
             } else {
@@ -179,11 +178,8 @@ impl Operator for Sub {
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
 
-        if arguments[0].is_int() && arguments[1].is_int() {
+        if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-            let result = arguments[0]
+            let result = a.checked_sub(b);
-                .as_int()
-                .unwrap()
-                .checked_sub(arguments[1].as_int().unwrap());
             if let Some(result) = result {
                 Ok(Value::Int(result))
             } else {
@@ -217,8 +213,8 @@ impl Operator for Neg {
         expect_operator_argument_amount(arguments.len(), 1)?;
         expect_number(&arguments[0])?;
 
-        if arguments[0].is_int() {
+        if let Ok(a) = arguments[0].as_int() {
-            let result = arguments[0].as_int().unwrap().checked_neg();
+            let result = a.checked_neg();
             if let Some(result) = result {
                 Ok(Value::Int(result))
             } else {
@@ -248,11 +244,8 @@ impl Operator for Mul {
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
 
-        if arguments[0].is_int() && arguments[1].is_int() {
+        if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-            let result = arguments[0]
+            let result = a.checked_mul(b);
-                .as_int()
-                .unwrap()
-                .checked_mul(arguments[1].as_int().unwrap());
             if let Some(result) = result {
                 Ok(Value::Int(result))
             } else {
@@ -287,11 +280,8 @@ impl Operator for Div {
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
 
-        if arguments[0].is_int() && arguments[1].is_int() {
+        if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-            let result = arguments[0]
+            let result = a.checked_div(b);
-                .as_int()
-                .unwrap()
-                .checked_div(arguments[1].as_int().unwrap());
             if let Some(result) = result {
                 Ok(Value::Int(result))
             } else {
@@ -326,11 +316,8 @@ impl Operator for Mod {
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
 
-        if arguments[0].is_int() && arguments[1].is_int() {
+        if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-            let result = arguments[0]
+            let result = a.checked_rem(b);
-                .as_int()
-                .unwrap()
-                .checked_rem(arguments[1].as_int().unwrap());
             if let Some(result) = result {
                 Ok(Value::Int(result))
             } else {
@@ -440,8 +427,8 @@ impl Operator for Gt {
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
 
-        if arguments[0].is_int() && arguments[1].is_int() {
+        if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-            if arguments[0].as_int().unwrap() > arguments[1].as_int().unwrap() {
+            if a > b {
                 Ok(Value::Boolean(true))
             } else {
                 Ok(Value::Boolean(false))
@@ -474,8 +461,8 @@ impl Operator for Lt {
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
 
-        if arguments[0].is_int() && arguments[1].is_int() {
+        if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-            if arguments[0].as_int().unwrap() < arguments[1].as_int().unwrap() {
+            if a < b {
                 Ok(Value::Boolean(true))
             } else {
                 Ok(Value::Boolean(false))
@@ -508,8 +495,8 @@ impl Operator for Geq {
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
 
-        if arguments[0].is_int() && arguments[1].is_int() {
+        if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-            if arguments[0].as_int().unwrap() >= arguments[1].as_int().unwrap() {
+            if a >= b {
                 Ok(Value::Boolean(true))
             } else {
                 Ok(Value::Boolean(false))
@@ -542,8 +529,8 @@ impl Operator for Leq {
         expect_number(&arguments[0])?;
         expect_number(&arguments[1])?;
 
-        if arguments[0].is_int() && arguments[1].is_int() {
+        if let (Ok(a), Ok(b)) = (arguments[0].as_int(), arguments[1].as_int()) {
-            if arguments[0].as_int().unwrap() <= arguments[1].as_int().unwrap() {
+            if a <= b {
                 Ok(Value::Boolean(true))
             } else {
                 Ok(Value::Boolean(false))

src/tree/mod.rs

@@ -20,7 +20,7 @@ mod display;
 ///
 /// let mut configuration = HashMapConfiguration::new();
 /// configuration.insert_variable("alpha", 2);
-/// let node = build_operator_tree("1 + alpha").unwrap();
+/// let node = build_operator_tree("1 + alpha").unwrap(); // Do proper error handling here
 /// assert_eq!(node.eval_with_configuration(&configuration), Ok(Value::from(3)));
 /// ```
 ///
@@ -290,14 +290,18 @@ pub(crate) fn tokens_to_operator_tree(tokens: Vec<Token>) -> Result<Node, Error>
 
     if root.len() > 1 {
         Err(Error::UnmatchedLBrace)
-    } else if root.len() == 0 {
+    } else if let Some(mut root) = root.pop() {
-        Err(Error::UnmatchedRBrace)
+        if root.children().len() > 1 {
-    } else {
+            Err(Error::wrong_operator_argument_amount(
-        let mut root = root.pop().unwrap();
+                root.children().len(),
-        if root.children().len() == 1 {
+                1,
-            Ok(root.children.pop().unwrap())
+            ))
+        } else if let Some(child) = root.children.pop() {
+            Ok(child)
         } else {
             Err(Error::EmptyExpression)
         }
+    } else {
+        Err(Error::UnmatchedRBrace)
     }
 }

src/value/mod.rs

@@ -159,15 +159,15 @@ mod tests {
     #[test]
     fn test_value_conversions() {
         assert_eq!(
-            Value::from("string").as_string().unwrap(),
+            Value::from("string").as_string(),
-            String::from("string")
+            Ok(String::from("string"))
         );
-        assert_eq!(Value::from(3).as_int().unwrap(), 3);
+        assert_eq!(Value::from(3).as_int(), Ok(3));
-        assert_eq!(Value::from(3.3).as_float().unwrap(), 3.3);
+        assert_eq!(Value::from(3.3).as_float(), Ok(3.3));
-        assert_eq!(Value::from(true).as_boolean().unwrap(), true);
+        assert_eq!(Value::from(true).as_boolean(), Ok(true));
         assert_eq!(
-            Value::from(TupleType::new()).as_tuple().unwrap(),
+            Value::from(TupleType::new()).as_tuple(),
-            TupleType::new()
+            Ok(TupleType::new())
         );
     }