Fixed minus printing

src/quantity/mod.rs

@@ -3,5 +3,5 @@ mod rationalq;
 pub mod quantity;
 pub use crate::quantity::quantity::Quantity;
 
-const FLOAT_PRECISION: u32 = 2048;
+const FLOAT_PRECISION: u32 = 1024;
 const PRINT_LEN: usize = 5; // How many significant digits we will show in output

src/quantity/quantity.rs

@@ -246,6 +246,20 @@ impl Quantity {
 			Quantity::Rational { .. } => {panic!()}
 		}
 	}
+
+	pub fn is_negative(&self) -> bool {
+		match self {
+			Quantity::Float { v } => {v.is_sign_negative() && v.is_normal()},
+			Quantity::Rational { v } => {v.is_negative()}
+		}
+	}
+
+	pub fn is_positive(&self) -> bool {
+		match self {
+			Quantity::Float { v } => {v.is_sign_positive() && v.is_normal()},
+			Quantity::Rational { v } => {v.is_positive()}
+		}
+	}
 }
 
 impl Neg for Quantity where {

src/quantity/rationalq.rs

@@ -86,6 +86,9 @@ impl RationalQ {
 	}
 
 
+	pub fn is_negative(&self) -> bool { self.val.clone().signum() == -1 }
+	pub fn is_positive(&self) -> bool { self.val.clone().signum() == 1 }
+
 	pub fn exp(&self) -> Quantity {float!(self.to_float().exp())}
 
 	pub fn abs(&self) -> Quantity {rational!(self.val.clone().abs())}

src/tokens.rs

@@ -300,18 +300,26 @@ impl Operator {
 				let mut b = &args[1];
 				let mut sub = false;
 
+				let tmp;
+
 				if let Token::Operator(o,ar) = b {
 					if let Operator::Negative = o {
 						sub = true;
 						b = &ar[0];
 					}
+				} else if let Token::Number(q) = b {
+					if q.is_negative() {
+						sub = true;
+						tmp = Token::Number(-q.clone());
+						b = &tmp;
+					}
 				}
 				let (b, sub) = (b, sub);
 
 				if sub {
-					return format!("{} - {}", self.add_parens_to_arg(a), self.add_parens_to_arg(b));
+					return format!("{} - {}", self.add_parens_to_arg(a), self.add_parens_to_arg(&b));
 				} else {
-					return format!("{} + {}", self.add_parens_to_arg(a), self.add_parens_to_arg(b));
+					return format!("{} + {}", self.add_parens_to_arg(a), self.add_parens_to_arg(&b));
 				}
 			},
 			
@@ -435,11 +443,17 @@ impl Operator {
 				if args.len() != 2 { panic!() }
 				let a = args.pop_front().unwrap();
 				let b = args.pop_front().unwrap();
-				let b = Token::Operator(Operator::Negative, VecDeque::from(vec!(b)));
+
+				let b_new;
+				if let Token::Number(q) = b {
+					b_new = Token::Number(-q);
+				} else {
+					b_new = Token::Operator(Operator::Negative, VecDeque::from(vec!(b)));
+				}
 
 				Token::Operator(
 					Operator::Add,
-					VecDeque::from(vec!(a,b))
+					VecDeque::from(vec!(a,b_new))
 				)
 			},