Add README.md

README.md

@@ -0,0 +1,100 @@
+Metrify
+=======
+Metrify is a tool for converting commonly-used non-metric units to metric.
+
+Usage
+-----
+Simplest way to use metrify is to invoke it with an expression in terms of
+non-metric units as its arguments:
+
+    metrify 1.4 short tons
+
+The expression can contain several number + unit sequences, which are summed
+together if the units are compatible:
+
+    metrify 5′8″
+    metrify 1 acre 15 square feet
+
+You can also invoke metrify without arguments, in which case it will give you a
+prompt to type the expression into.
+
+Result display
+--------------
+Metrify will pick the appropriate prefix for the given result and unit
+automatically. The value is rounded so that results <1 have 4 digits, <10 3
+digits, <100 2 digits, <1000 1 digit and ≥1000 no digits after the decimal
+point. The digits before the decimal point are grouped into groups of three.
+
+	0.4929 ml
+	1.609 km
+	28.35 g
+	907.2 kg
+	28 317 cm³
+
+Supported units
+---------------
+
+### Length units based on the international yard
+
+* inch (in)
+* foot (ft)
+* yard (yd)
+* mile (mi)
+
+### Mass units based on the international pound
+
+* ounce (oz)
+* pound (lb)
+* stone (st)
+* short ton
+* long ton
+
+### Temperature
+
+* Degrees Fahrenheit (°F)
+
+### Area units based on the international yard
+
+* square inch (in²)
+* square foot (ft²)
+* acre (ac)
+* square mile (mi²)
+
+### Volume units based on the international yard
+
+* cubic inch (in³)
+* cubic foot (ft³)
+
+### Imperial fluid volume units
+
+* imperial fluid ounce (imp fl oz)
+* imperial pint (imp pt)
+* imperial quart (imp qt)
+* imperial gallon (imp gal)
+
+### US customary fluid volume units
+
+* US teaspoon (tsp)
+* US tablespoon (tbsp)
+* US fluid ounce (us fl oz)
+* US cup (cup)
+* US pint (us pt)
+* US quart (us qt)
+* US gallon (us gal)
+
+Why should I use metrify instead of units(1)?
+---------------------------------------------
+Metrify is more special-purpose than units(1), which allows it to present the
+user a nicer interface for the purposes it does support. For example with
+metrify you do not need to explicitly tell it the unit you are converting to,
+because due to its requirements (conversion is always from non-metric to metric)
+it can automatically pick the correct one.
+
+Building and installation
+-------------------------
+You can build and test out metrify with `cargo run`. If you want to install it
+locally, you can use `cargo install --path .` in the source directory.
+
+License
+-------
+Metrify is under Creative Commons Zero 1.0.

src/conversions.rs

@@ -48,7 +48,7 @@ fn get_conversion(unit: NonMetric) -> Conversion {
 			from: inch_from,
 			to: MetricQuantity { amount: 1760.0 * 3.0 * 12.0 * inch_to, unit: Metric::Metre },
 		},
-		// Weight
+		// Mass
 		NonMetric::Ounce => Conversion {
 			offset: 0.0,
 			from: 16.0 * pound_from,
@@ -189,7 +189,7 @@ mod test {
 	}
 
 	#[test]
-	fn weight() {
+	fn mass() {
 		let tests = [
 			Test(NonMetric::Ounce, 28.349523125),
 			Test(NonMetric::Pound, 453.59237),

src/lib.rs

@@ -73,7 +73,7 @@ fn unit_to_name(unit: NonMetric) -> &'static str {
 		NonMetric::Foot => "feet",
 		NonMetric::Yard => "yards",
 		NonMetric::Mile => "miles",
-		// Weight
+		// Mass
 		NonMetric::Ounce => "ounces",
 		NonMetric::Pound => "pounds",
 		NonMetric::Stone => "stones",
@@ -127,7 +127,7 @@ mod test {
 		assert_eq!(run("1 ft"), Ok("30.48 cm".to_string()));
 		assert_eq!(run("1 yard"), Ok("91.44 cm".to_string()));
 		assert_eq!(run("1 mile"), Ok("1.609 km".to_string()));
-		// Weight
+		// Mass
 		assert_eq!(run("1 oz"), Ok("28.35 g".to_string()));
 		assert_eq!(run("1 lb"), Ok("453.6 g".to_string()));
 		assert_eq!(run("1 st"), Ok("6.35 kg".to_string()));

src/parse.rs

@@ -83,7 +83,7 @@ fn parse_unit(input: String) -> Result<NonMetric, ParseError> {
 		"mi" => Ok(NonMetric::Mile),
 		"m" => Ok(NonMetric::Mile),
 
-		// Weight
+		// Mass
 		"ounce" => Ok(NonMetric::Ounce),
 		"ounces" => Ok(NonMetric::Ounce),
 		"oz" => Ok(NonMetric::Ounce),
@@ -263,6 +263,8 @@ fn parse_unit(input: String) -> Result<NonMetric, ParseError> {
 		"US cups" => Ok(NonMetric::USCup),
 		"us cup" => Ok(NonMetric::USCup),
 		"us cups" => Ok(NonMetric::USCup),
+		"cup" => Ok(NonMetric::USCup),
+		"cups" => Ok(NonMetric::USCup),
 
 		"US liquid pint" => Ok(NonMetric::USLiquidPint),
 		"US liquid pints" => Ok(NonMetric::USLiquidPint),
@@ -459,7 +461,7 @@ mod test {
 			"m",
 		]);
 
-		// Weight
+		// Mass
 		test_units(NonMetric::Ounce, &[
 			"ounce",
 			"ounces",
@@ -678,6 +680,8 @@ mod test {
 			"US cups",
 			"us cup",
 			"us cups",
+			"cup",
+			"cups",
 		]);
 
 		test_units(NonMetric::USLiquidPint, &[

src/units.rs

@@ -15,7 +15,7 @@ pub enum NonMetric {
 	Foot,
 	Yard,
 	Mile,
-	// Weight
+	// Mass
 	Ounce,
 	Pound,
 	Stone,