From a1ba0546092029cde45fb2caa441a995b2e9e63b Mon Sep 17 00:00:00 2001
From: Sebastian Schmidt <isibboi@gmail.com>
Date: Fri, 15 Mar 2019 18:34:40 +0200
Subject: [PATCH] Implemented mod and replaced Braced with RootNode

---
 src/lib.rs          |  7 ++++++
 src/operator/mod.rs | 52 ++++++++++++++++++++++++++++-----------------
 src/token/mod.rs    |  3 +++
 src/tree/mod.rs     |  7 ++----
 4 files changed, 45 insertions(+), 24 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index d0166ee..6f90b4c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -82,6 +82,13 @@ mod test {
         assert_eq!(eval("7/(7/(7/(7/(7/(7)))))"), Ok(Value::Int(1)));
     }
 
+    #[test]
+    fn test_mod_examples() {
+        assert_eq!(eval("1 % 4"), Ok(Value::Int(1)));
+        assert_eq!(eval("6 % 4"), Ok(Value::Int(2)));
+        assert_eq!(eval("1 % 4 + 2"), Ok(Value::Int(3)));
+    }
+
     #[test]
     fn test_type_errors() {
         assert_eq!(
diff --git a/src/operator/mod.rs b/src/operator/mod.rs
index 350c153..a029e95 100644
--- a/src/operator/mod.rs
+++ b/src/operator/mod.rs
@@ -21,12 +21,14 @@ pub trait Operator {
 }
 
 pub struct RootNode;
+pub struct Braced;
+
 pub struct Add;
 pub struct Sub;
 pub struct Neg;
 pub struct Mul;
 pub struct Div;
-pub struct Braced;
+pub struct Mod;
 
 pub struct Const {
     value: Value,
@@ -50,15 +52,16 @@ impl Identifier {
 
 impl Operator for RootNode {
     fn precedence(&self) -> i32 {
-        i32::min_value()
+        200
     }
 
     fn argument_amount(&self) -> usize {
         1
     }
 
-    fn eval(&self, _arguments: &[Value], _configuration: &Configuration) -> Result<Value, Error> {
-        Err(Error::EvaluatedRootNode)
+    fn eval(&self, arguments: &[Value], _configuration: &Configuration) -> Result<Value, Error> {
+        expect_argument_amount(arguments.len(), 1)?;
+        Ok(arguments[0].clone())
     }
 }
 
@@ -187,6 +190,32 @@ impl Operator for Div {
     }
 }
 
+impl Operator for Mod {
+    fn precedence(&self) -> i32 {
+        100
+    }
+
+    fn argument_amount(&self) -> usize {
+        2
+    }
+
+    fn eval(&self, arguments: &[Value], _configuration: &Configuration) -> Result<Value, Error> {
+        expect_argument_amount(arguments.len(), 2)?;
+        expect_number(&arguments[0])?;
+        expect_number(&arguments[1])?;
+
+        if arguments[0].is_int() && arguments[1].is_int() {
+            Ok(Value::Int(
+                arguments[0].as_int().unwrap() % arguments[1].as_int().unwrap(),
+            ))
+        } else {
+            Ok(Value::Float(
+                arguments[0].as_float().unwrap() % arguments[1].as_float().unwrap(),
+            ))
+        }
+    }
+}
+
 impl Operator for Const {
     fn precedence(&self) -> i32 {
         200
@@ -218,18 +247,3 @@ impl Operator for Identifier {
         configuration.get_value(&self.identifier)
     }
 }
-
-impl Operator for Braced {
-    fn precedence(&self) -> i32 {
-        200
-    }
-
-    fn argument_amount(&self) -> usize {
-        1
-    }
-
-    fn eval(&self, arguments: &[Value], configuration: &Configuration) -> Result<Value, Error> {
-        expect_argument_amount(arguments.len(), 1)?;
-        Ok(arguments[0].clone())
-    }
-}
diff --git a/src/token/mod.rs b/src/token/mod.rs
index 7605e85..ee344eb 100644
--- a/src/token/mod.rs
+++ b/src/token/mod.rs
@@ -7,6 +7,7 @@ pub enum Token {
     Minus,
     Star,
     Slash,
+    Percent,
     LBrace,
     RBrace,
     Whitespace,
@@ -30,6 +31,7 @@ fn char_to_token(c: char) -> PartialToken {
         '-' => PartialToken::Token(Token::Minus),
         '*' => PartialToken::Token(Token::Star),
         '/' => PartialToken::Token(Token::Slash),
+        '%' => PartialToken::Token(Token::Percent),
         '(' => PartialToken::Token(Token::LBrace),
         ')' => PartialToken::Token(Token::RBrace),
         c => {
@@ -50,6 +52,7 @@ impl Token {
             Token::Minus => false,
             Token::Star => false,
             Token::Slash => false,
+            Token::Percent => false,
             Token::LBrace => false,
             Token::RBrace => true,
             Token::Whitespace => false,
diff --git a/src/tree/mod.rs b/src/tree/mod.rs
index e10e230..c42c1b5 100644
--- a/src/tree/mod.rs
+++ b/src/tree/mod.rs
@@ -17,10 +17,6 @@ impl Node {
     fn root_node() -> Self {
         Self::new(RootNode)
     }
-    
-    fn braced_node() -> Self {
-        Self::new(Braced)
-    }
 
     pub fn eval(&self, configuration: &Configuration) -> Result<Value, Error> {
         let mut arguments = Vec::new();
@@ -91,8 +87,9 @@ pub fn tokens_to_operator_tree(tokens: Vec<Token>) -> Result<Node, Error> {
             }
             Token::Star => Some(Node::new(Mul)),
             Token::Slash => Some(Node::new(Div)),
+            Token::Percent => Some(Node::new(Mod)),
             Token::LBrace => {
-                root.push(Node::braced_node());
+                root.push(Node::root_node());
                 None
             },
             Token::RBrace => {