What is the purpose of overriding a trait function with a class value in Scala?

Ask Time：2015-07-29T12:08:00 Author：Luong Ba Linh

I am new to Scala. I just wonder why we sometimes, especially in Scala API, override trait function with a class value like the example below:

sealed trait Amount {
  def amount: Double
}

case class Percentage(amount: Double) extends Amount {
  override def toString = s"$amount%"
}

Author:Luong Ba Linh，eproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/31691073/what-is-the-purpose-of-overriding-a-trait-function-with-a-class-value-in-scala

More about “What is the purpose of overriding a trait function with a class value in Scala?” related questions

What is the purpose of overriding a trait function with a class value in Scala?

I am new to Scala. I just wonder why we sometimes, especially in Scala API, override trait function with a class value like the example below: sealed trait Amount { def amount: Double } case cl...
Purpose of Scala trait extending AnyVal?

Sometimes in Scala/Scala.js I see trait Foo extends AnyVal { ... } – what's the meaning and purpose of extends AnyVal here? I'm aware of value classes, and that they can not extend traits that ext...
what's the purpose of an empty trait in scala

In Action.scala from play framework, it has the following code, why it defines a trait "Handler" without any method or field, what's the purpose or benefit of defining an empty trait? trait Handle...
Recursive call of `val` in scala trait?

I am trying to debug a scala program. I found a trait which behavior is similar to following: trait A { val a: Int = b val b: Int = a } class B extends A If we look at the trait there is ...
Why can a Scala trait extend a class?

I see that traits in Scala are similar to interfaces in Java (but interfaces in Java extend other interfaces, they don't extend a class). I saw an example on SO about traits usage where a trait ext...
Can I override a scala class method with a method from a trait?

class PasswordCaseClass(val password:String) trait PasswordTrait { self:PasswordCaseClass => override def password = "blue" } val o = new PasswordCaseClass("flowers") with PasswordTrait Is...
What is the purpose of AbstractSystem trait in akka-spray-websocket activator?

I'm learning Spray and Akka. And I'm learning it through TypeSafe's templates, and this one is very complex at least: http://typesafe.com/activator/template/akka-spray-websocket I now understand ...
Selecting trait to inherit common method from in Scala

Suppose that I create a class mixing in two traits, both of which implement a common method, as follows for instance: abstract class Base { var x:Int def adder:Int } trait One extends Bas...
value foo in class MyJavaClass of type java.lang.String has incompatible type mixing in Java class and Scala trait

I have a Scala trait trait MyTrait{ val foo: String def bar = foo } and a Java class that provides foo public class MyJavaClass { public final String foo = "hello"; } Now I try to
Overriding the method of a generic trait in Scala

I defined a generic Environment trait: trait Environment[T] For which I provide this implementation: class MyEnvironment extends Environment[Integer] { val specific: Integer = 0 } Furthermore, I

What is the purpose of overriding a trait function with a class value in Scala?

What is the purpose of overriding a trait function with a class value in Scala?

Purpose of Scala trait extending AnyVal?

what's the purpose of an empty trait in scala

Recursive call of `val` in scala trait?

Why can a Scala trait extend a class?

Can I override a scala class method with a method from a trait?

What is the purpose of AbstractSystem trait in akka-spray-websocket activator?

Selecting trait to inherit common method from in Scala

value foo in class MyJavaClass of type java.lang.String has incompatible type mixing in Java class and Scala trait

Overriding the method of a generic trait in Scala

热门文章

jpg图片怎么转换成pdf，详细教程分享！

iphone怎么把图片转成电子版？试试这2个方法！

图片如何转换pdf文件？看看这三个方法！

怎么把图片转换成pdf格式，干货教程不要错过

png图片怎么转换成pdf，实用方法不要错过

图片怎么转pdf格式？三种转换方法分享给你，一分钟轻松解决

图片转pdf格式怎么弄免费？get这五个简单的方法，轻松搞定！

如何将图片转pdf格式？4种转换方法分享给你，一分钟轻松解决

如何图片转pdf免费？快学习这三种免费转换方法

怎么将图片转pdf？分享个图片转pdf在线免费

相关搜索

jpg图片怎么转换成pdf，详细教程分享

电脑图片转pdf工具怎么用

单张pdf图片转照片格式

如何将图片转成pdf文档，经验分享

这么好用的图片转pdf软件，我一定要分享

干货分享，不懂图片转pdf的朋友快快收藏起来

分享一个让你惊叹不已的图片转pdf方法

图片转pdf工具

分享一个大家都不知道的图片转pdf格式方法

好用的图片转pdf软件要和好朋友分享