Fixed mph/mpg behavior

Cargo.lock

@@ -22,7 +22,7 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "daisy"
-version = "0.2.1"
+version = "0.2.2"
 dependencies = [
  "cfg-if",
  "rug",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "daisy"
-version = "0.2.1"
+version = "0.2.2"
 edition = "2021"
 
 [profile.release]

src/evaluate/constant.rs

@@ -1,6 +1,7 @@
 use crate::parser::Token;
 use crate::parser::Constant;
 use crate::quantity::Quantity;
+use crate::quantity::Unit;
 
 use super::EvalError;
 
@@ -19,5 +20,27 @@ pub fn eval_constant(c: &Constant) -> Result<Token, EvalError> {
 		Constant::Phi => { Token::Quantity(Quantity::new_float_from_string(
 			"1.618033988749894848204586834365638117720309179805762862135448622705260462818902449707207204189391137"
 		).unwrap()) },
+
+		Constant::MPG => {
+			let mut q = Quantity::new_float_from_string("1").unwrap();
+			q.set_unit(
+				(
+					Unit::from_string("mile").unwrap() /
+					Unit::from_string("gallon").unwrap()
+				).unit
+			);
+			Token::Quantity(q)
+		},
+
+		Constant::MPH => {
+			let mut q = Quantity::new_float_from_string("1").unwrap();
+			q.set_unit(
+				(
+					Unit::from_string("mile").unwrap() /
+					Unit::from_string("hour").unwrap()
+				).unit
+			);
+			Token::Quantity(q)
+		},
 	})
 }

src/parser/pretoken.rs

@@ -78,6 +78,8 @@ impl PreToken {
 					"π"|"pi" => { Some(Constant::Pi)},
 					"e" => { Some(Constant::E) },
 					"phi"|"φ" => { Some(Constant::Phi) },
+					"mpg" => { Some(Constant::MPG) },
+					"mph" => { Some(Constant::MPH) },
 					_ => { None }
 				};
 

src/parser/token/constant.rs

@@ -1,17 +1,27 @@
 #[derive(Debug)]
 #[derive(Clone)]
 pub enum Constant {
+	// Fake units
+	MPG,
+	MPH,
+
+	// Mathematics
 	Pi,
 	Phi,
-	E
+	E,
 }
 
 impl Constant {
 	pub fn to_string(&self) -> String {
 		match self {
+			// Fake units
+			Constant::MPG => { String::from("mpg") },
+			Constant::MPH => { String::from("mph") },
+
+			// Mathematics
 			Constant::Pi => { String::from("π") },
 			Constant::Phi => { String::from("φ") },
-			Constant::E => { String::from("e") },
+			Constant::E => { String::from("e") }
 		}
 	}
 }

src/quantity/unit/mod.rs

@@ -39,8 +39,6 @@ pub enum UnitBase {
 	// Area
 	Barn,
 	Hectare,
-	MilesPerHour,
-	MilesPerGallon,
 	Acre,
 
 
@@ -190,8 +188,6 @@ macro_rules! fromstring_db {
 			(UnitBase::JulianYear, "julianYears"),
 
 			// Misc
-			(UnitBase::MilesPerHour, "mph"),
-			(UnitBase::MilesPerGallon, "mpg"),
 			(UnitBase::Barn, "b"),
 			(UnitBase::Barn, "barn"),
 			(UnitBase::Hectare, "ha"),
@@ -346,7 +342,7 @@ macro_rules! unit_db {
 			),
 
 			UnitBase::Hour => $X!(
-				UnitBase::Hour, "hour",
+				UnitBase::Hour, "h",
 				rational, "3600",
 				(UnitBase::Second, 1f64)
 			),
@@ -457,21 +453,6 @@ macro_rules! unit_db {
 				(UnitBase::Meter, 1f64)
 			),
 
-
-			// Misc
-			UnitBase::MilesPerHour => $X!(
-				UnitBase::MilesPerHour, "mph",
-				float, "0.44704",
-				(UnitBase::Meter, 1f64),
-				(UnitBase::Second, -1f64)
-			),
-
-			UnitBase::MilesPerGallon => $X!(
-				UnitBase::MilesPerGallon, "mpg",
-				float, "425144",
-				(UnitBase::Meter, -2f64)
-			),
-
 			UnitBase::Barn => $X!(
 				UnitBase::Barn, "b",
 				rational, "1e-28",

src/tests.rs

@@ -206,5 +206,6 @@ fn basic_units() {
 fn complex_units() {
 	good_expr("0.62137 mi", "1km to mi");
 	good_expr("3280.8 ft", "1km to ft");
-	good_expr("62.137 mph", "100 km/h to mph");
+	good_expr("62.137 mi/h", "100 km/h to mph");
+	good_expr("20 mi", "10 mph * 2 hours");
 }