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Length final ​

finalclassLengthextendsQuantity<Length>

A quantity representing length or distance.

Inheritance

Object → Quantity<A extends Quantity<A>> → Length

Constructors ​

Length() ​

Length(doublevalue,UnitOfMeasure<Length>unit)
Implementation
dart
Length(super.value, super.unit);

Properties ​

hashCode no setter inherited ​

intgethashCode

The hash code for this object.

A hash code is a single integer which represents the state of the object that affects operator == comparisons.

All objects have hash codes. The default hash code implemented by Object represents only the identity of the object, the same way as the default operator == implementation only considers objects equal if they are identical (see identityHashCode).

If operator == is overridden to use the object state instead, the hash code must also be changed to represent that state, otherwise the object cannot be used in hash based data structures like the default Set and Map implementations.

Hash codes must be the same for objects that are equal to each other according to operator ==. The hash code of an object should only change if the object changes in a way that affects equality. There are no further requirements for the hash codes. They need not be consistent between executions of the same program and there are no distribution guarantees.

Objects that are not equal are allowed to have the same hash code. It is even technically allowed that all instances have the same hash code, but if clashes happen too often, it may reduce the efficiency of hash-based data structures like HashSet or HashMap.

If a subclass overrides hashCode, it should override the operator == operator as well to maintain consistency.

Inherited from Quantity.

Implementation
dart
@override
int get hashCode => Object.hash(value, unit);

runtimeType no setter inherited ​

TypegetruntimeType

A representation of the runtime type of the object.

Inherited from Object.

Implementation
dart
external Type get runtimeType;

toCentimeters no setter ​

LengthgettoCentimeters

Converts this to centimeters (cm).

Implementation
dart
Length get toCentimeters => to(centimeters).centimeters;

toDecameters no setter ​

LengthgettoDecameters

Converts this to decameters (dam).

Implementation
dart
Length get toDecameters => to(decameters).decameters;

toDecimeters no setter ​

LengthgettoDecimeters

Converts this to decimeters (dm).

Implementation
dart
Length get toDecimeters => to(decimeters).decimeters;

toFeet no setter ​

LengthgettoFeet

Converts this to feet (ft).

Implementation
dart
Length get toFeet => to(feet).feet;

toHectometers no setter ​

LengthgettoHectometers

Converts this to hectometers (hm).

Implementation
dart
Length get toHectometers => to(hectometers).hectometers;

toInches no setter ​

LengthgettoInches

Converts this to inches (in).

Implementation
dart
Length get toInches => to(inches).inches;

toKilometers no setter ​

LengthgettoKilometers

Converts this to kilometers (km).

Implementation
dart
Length get toKilometers => to(kilometers).kilometers;

toMeters no setter ​

LengthgettoMeters

Converts this to meters (m).

Implementation
dart
Length get toMeters => to(meters).meters;

toMicrons no setter ​

LengthgettoMicrons

Converts this to microns (µm).

Implementation
dart
Length get toMicrons => to(microns).microns;

toMillimeters no setter ​

LengthgettoMillimeters

Converts this to millimeters (mm).

Implementation
dart
Length get toMillimeters => to(millimeters).millimeters;

toNanometers no setter ​

LengthgettoNanometers

Converts this to nanometers (nm).

Implementation
dart
Length get toNanometers => to(nanometers).nanometers;

toNauticalMiles no setter ​

LengthgettoNauticalMiles

Converts this to nautical miles (nmi).

Implementation
dart
Length get toNauticalMiles => to(nauticalMiles).nauticalMiles;

toUsMiles no setter ​

LengthgettoUsMiles

Converts this to US miles (mi).

Implementation
dart
Length get toUsMiles => to(usMiles).usMiles;

toYards no setter ​

LengthgettoYards

Converts this to yards (yd).

Implementation
dart
Length get toYards => to(yards).yards;

unit final inherited ​

The unit of measure that value is expressed in.

Inherited from Quantity.

Implementation
dart
final UnitOfMeasure<A> unit;

value final inherited ​

finaldoublevalue

The raw numeric value of this quantity expressed in unit.

Inherited from Quantity.

Implementation
dart
final double value;

Methods ​

equivalentTo() inherited ​

boolequivalentTo(Quantity<Length>other)

Returns true if this quantity represents the same physical magnitude as other, regardless of which unit each is expressed in.

Inherited from Quantity.

Implementation
dart
bool equivalentTo(Quantity<A> other) => other.to(unit) == value;

noSuchMethod() inherited ​

dynamicnoSuchMethod(Invocationinvocation)

Invoked when a nonexistent method or property is accessed.

A dynamic member invocation can attempt to call a member which doesn't exist on the receiving object. Example:

dart
dynamic object = 1;
object.add(42); // Statically allowed, run-time error

This invalid code will invoke the noSuchMethod method of the integer 1 with an Invocation representing the .add(42) call and arguments (which then throws).

Classes can override noSuchMethod to provide custom behavior for such invalid dynamic invocations.

A class with a non-default noSuchMethod invocation can also omit implementations for members of its interface. Example:

dart
class MockList<T> implements List<T> {
  noSuchMethod(Invocation invocation) {
    log(invocation);
    super.noSuchMethod(invocation); // Will throw.
  }
}
void main() {
  MockList().add(42);
}

This code has no compile-time warnings or errors even though the MockList class has no concrete implementation of any of the List interface methods. Calls to List methods are forwarded to noSuchMethod, so this code will log an invocation similar to Invocation.method(#add, [42]) and then throw.

If a value is returned from noSuchMethod, it becomes the result of the original invocation. If the value is not of a type that can be returned by the original invocation, a type error occurs at the invocation.

The default behavior is to throw a NoSuchMethodError.

Inherited from Object.

Implementation
dart
@pragma("vm:entry-point")
@pragma("wasm:entry-point")
external dynamic noSuchMethod(Invocation invocation);

to() inherited ​

doubleto(UnitOfMeasure<Length>uom)

Converts this quantity to uom and returns the raw double value.

If uom equals unit, the current value is returned unchanged.

Inherited from Quantity.

Implementation
dart
double to(UnitOfMeasure<A> uom) => uom == unit ? value : uom.convertTo(unit.convertFrom(value));

toString() inherited ​

StringtoString()

A string representation of this object.

Some classes have a default textual representation, often paired with a static parse function (like int.parse). These classes will provide the textual representation as their string representation.

Other classes have no meaningful textual representation that a program will care about. Such classes will typically override toString to provide useful information when inspecting the object, mainly for debugging or logging.

Inherited from Quantity.

Implementation
dart
@override
String toString() => '$value ${unit.symbol}';

Operators ​

operator *() ​

Areaoperator *(Lengththat)

Multiplies this length by that to produce an Area.

The result unit is chosen to match the unit of this where possible (e.g. feet * feet → squareFeet); otherwise defaults to square meters.

Implementation
dart
Area operator *(Length that) {
  if (unit == centimeters) {
    return Area.squareCentimeters(value * that.toCentimeters.value);
  } else if (unit == kilometers) {
    return Area.squareKilometers(value * that.toKilometers.value);
  } else if (unit == usMiles) {
    return Area.squareUsMiles(value * that.toUsMiles.value);
  } else if (unit == yards) {
    return Area.squareYards(value * that.toYards.value);
  } else if (unit == feet) {
    return Area.squareFeet(value * that.toFeet.value);
  } else if (unit == inches) {
    return Area.squareInches(value * that.toInches.value);
  } else {
    return Area.squareMeters(toMeters.value * that.toMeters.value);
  }
}

operator +() inherited ​

Lengthoperator +(Lengththat)

Returns the sum of this quantity and that, expressed in unit.

that is converted to unit before adding, so mixed-unit addition is safe.

Inherited from Quantity.

Implementation
dart
A operator +(A that) => unit.call(value + that.to(unit));

operator -() inherited ​

Lengthoperator -(Lengththat)

Returns the difference of this quantity and that, expressed in unit.

that is converted to unit before subtracting, so mixed-unit subtraction is safe.

Inherited from Quantity.

Implementation
dart
A operator -(A that) => unit.call(value - that.to(unit));

operator /() ​

Velocityoperator /(Timethat)

Divides this length by that time to produce a Velocity in m/s.

Implementation
dart
Velocity operator &#47;(Time that) => Velocity.metersPerSecond(toMeters.value &#47; that.toSeconds.value);

operator <() inherited ​

booloperator <(Lengththat)

Returns true if this quantity is less than that.

that is converted to unit before comparing.

Inherited from Quantity.

Implementation
dart
bool operator <(A that) => value < that.to(unit);

operator <=() inherited ​

booloperator <=(Lengththat)

Returns true if this quantity is less than or equal to that.

that is converted to unit before comparing.

Inherited from Quantity.

Implementation
dart
bool operator <=(A that) => value <= that.to(unit);

operator ==() inherited ​

booloperator ==(Objectother)

The equality operator.

The default behavior for all Objects is to return true if and only if this object and other are the same object.

Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:

  • Total: It must return a boolean for all arguments. It should never throw.

  • Reflexive: For all objects o, o == o must be true.

  • Symmetric: For all objects o1 and o2, o1 == o2 and o2 == o1 must either both be true, or both be false.

  • Transitive: For all objects o1, o2, and o3, if o1 == o2 and o2 == o3 are true, then o1 == o3 must be true.

The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.

If a subclass overrides the equality operator, it should override the hashCode method as well to maintain consistency.

Inherited from Quantity.

Implementation
dart
@override
bool operator ==(Object other) =>
    identical(this, other) ||
    (other is Quantity<A> && other.value == value && other.unit == unit);

operator >() inherited ​

booloperator >(Lengththat)

Returns true if this quantity is greater than that.

that is converted to unit before comparing.

Inherited from Quantity.

Implementation
dart
bool operator >(A that) => value > that.to(unit);

operator >=() inherited ​

booloperator >=(Lengththat)

Returns true if this quantity is greater than or equal to that.

that is converted to unit before comparing.

Inherited from Quantity.

Implementation
dart
bool operator >=(A that) => value >= that.to(unit);

Static Methods ​

parse() override ​

Option<Length>parse(Strings)

Parses s into a Length, returning None if parsing fails.

Implementation
dart
static Option<Length> parse(String s) => Quantity.parse(s, units);

Constants ​

centimeters ​

constLengthUnitcentimeters

Unit for centimeters (cm).

Implementation
dart
static const LengthUnit centimeters = Centimeters._();

decameters ​

constLengthUnitdecameters

Unit for decameters (dam).

Implementation
dart
static const LengthUnit decameters = Decameters._();

decimeters ​

constLengthUnitdecimeters

Unit for decimeters (dm).

Implementation
dart
static const LengthUnit decimeters = Decimeters._();

feet ​

constLengthUnitfeet

Unit for feet (ft).

Implementation
dart
static const LengthUnit feet = Feet._();

FeetConversionFactor ​

constdoubleFeetConversionFactor

Conversion factor from feet to meters.

Implementation
dart
static const FeetConversionFactor = 3.048006096e-1;

hectometers ​

constLengthUnithectometers

Unit for hectometers (hm).

Implementation
dart
static const LengthUnit hectometers = Hectometers._();

inches ​

constLengthUnitinches

Unit for inches (in).

Implementation
dart
static const LengthUnit inches = Inches._();

kilometers ​

constLengthUnitkilometers

Unit for kilometers (km).

Implementation
dart
static const LengthUnit kilometers = Kilometers._();

meters ​

constLengthUnitmeters

Unit for meters (m) — the SI base unit of length.

Implementation
dart
static const LengthUnit meters = Meters._();

microns ​

constLengthUnitmicrons

Unit for microns / micrometers (µm).

Implementation
dart
static const LengthUnit microns = Microns._();

millimeters ​

constLengthUnitmillimeters

Unit for millimeters (mm).

Implementation
dart
static const LengthUnit millimeters = Millimeters._();

nanometers ​

constLengthUnitnanometers

Unit for nanometers (nm).

Implementation
dart
static const LengthUnit nanometers = Nanometers._();

nauticalMiles ​

constLengthUnitnauticalMiles

Unit for nautical miles (nmi).

Implementation
dart
static const LengthUnit nauticalMiles = NauticalMiles._();

units ​

constSet<LengthUnit>units

All supported Length units.

Implementation
dart
static const units = {
  nanometers,
  microns,
  millimeters,
  centimeters,
  decimeters,
  meters,
  decameters,
  hectometers,
  kilometers,
  inches,
  feet,
  yards,
  usMiles,
  nauticalMiles,
};

usMiles ​

constLengthUnitusMiles

Unit for US survey miles (mi).

Implementation
dart
static const LengthUnit usMiles = UsMiles._();

yards ​

constLengthUnityards

Unit for yards (yd).

Implementation
dart
static const LengthUnit yards = Yards._();