case-class Questions

7

Solved

Is there an easy way to convert a case class into a tuple? I can, of course, easily write boilerplate code to do this, but I mean without the boilerplate. What I'm really after is a way to easily...
Coraliecoraline asked 10/11, 2011 at 23:42

7

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Scala case classes have a limit of 22 fields in the constructor. I want to exceed this limit, is there a way to do it with inheritance or composition that works with case classes?
Brimmer asked 28/11, 2013 at 5:32

1

Solved

I'd like to be able to store different related types in a Spark DataFrame but work with strongly typed case classes via a DataSet. E.g. say I have a Base trait and two case classes A and B that ext...

2

Solved

Assuming you have case classes like the following case class Test1(a:String,b:Int,c:Char) case class Test2(a:String,b:Int) And you instantiate the classes with the following variables val test...
Petrolatum asked 21/4, 2014 at 7:17

4

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In Scala, suppose I have a case class like this: case class Sample(myInt: Int, myString: String) Is there a way for me to obtain a Seq[(String, Class[_])], or better yet, Seq[(String, Manifest)]...
Randa asked 8/6, 2011 at 17:0

4

If I have the following case class with a private constructor and I can not access the apply-method in the companion object. case class Meter private (m: Int) val m = Meter(10) // constructor Met...
Cling asked 17/11, 2013 at 12:47

12

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Is there a nice way I can convert a Scala case class instance, e.g. case class MyClass(param1: String, param2: String) val x = MyClass("hello", "world") into a mapping of some kind, e.g. getCCP...
Grisham asked 4/8, 2009 at 9:40

11

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I'm making a parser with Scala Combinators. It is awesome. What I end up with is a long list of entagled case classes, like: ClassDecl(Complex,List(VarDecl(Real,float), VarDecl(Imag,float))), just ...
Are asked 30/3, 2013 at 12:27

17

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I searched in Google to find the differences between a case class and a class. Everyone mentions that when you want to do pattern matching on the class, use case class. Otherwise use classes and al...
Applegate asked 22/2, 2010 at 17:49

7

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I have a list of simple scala case class instances and I want to print them in predictable, lexicographical order using list.sorted, but receive "No implicit Ordering defined for ...". Is there ex...
Sophy asked 13/10, 2013 at 12:9

3

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I'm writing a type-safe code and want to replace apply() generated for case classes with my own implementation. Here it is: import shapeless._ sealed trait Data case object Remote extends Data cas...
Heterolysis asked 20/10, 2020 at 21:10

10

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So here's the situation. I want to define a case class like so: case class A(val s: String) and I want to define an object to ensure that when I create instances of the class, the value for 's' ...
Scenarist asked 29/4, 2011 at 3:25

1

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I'm trying to copy() a Scala case class which has a type param. At the call site, the type of the value is Foo[_]. This compiles as expected: case class Foo[A](id: String, name: String, v1: Bar[A])...

2

Solved

Defined empty trait Test: trait Test what used in compound type: scala> val a : Int with Test = 10.asInstanceOf[Int with Test] a: Int with Test = 10 and case class with parameter of compou...
Gond asked 20/11, 2013 at 11:28

1

I have a case class with many members, two of which are non-primitive: import com.twitter.util.Duration case class Foo( a: Int, b: Int, ..., y: Int, z: Int, timeoutSeconds: Duration, runtim...
Bridgework asked 29/11, 2014 at 4:35

1

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Assume I have case class with several field members: case class User(name: String, ..., createdAt: LocalDateTime) How could I check equality without taking into account createdAt field? Is there a...
Time asked 12/2, 2020 at 23:5

4

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Is there a elegant way to convert a case class to a CSV value. For example - case class Person( name : String, age : Int, gender: String, address : Option[String]) I was thinking about using ...
Underact asked 16/5, 2015 at 4:25

3

Solved

I have a case class with 2 String members. I would like to update The second member later, so first I create an instance with String and None and later I load the data to the class and would like t...
Obstacle asked 8/6, 2014 at 11:1

1

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Suppose there is a Scala case-class Point case class Point(x: Int, y: Int) One can use a wildcard for matching: val p = new Point(1,2) val inRightHalfPlane = p match { case Point(x, _) i...
Entozoon asked 8/5, 2019 at 15:28

2

Solved

I wrote the following: case class SuperMessage(message: String)(capitalMessage: String = message.capitalize) val message = "hello world" val superMessage = SuperMessage(message)() but I can't do...
Ferret asked 14/4, 2019 at 20:35

4

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Is there any way to easily parse a string of key value pairs into a scala case class? For example from the following string: "consumer_key=1234ABC, consumer_secret=12345ABC" into case class Au...
Kampala asked 25/10, 2012 at 13:30

0

I have an Enumeratum enum and need to load it into a spark data frame. Obviously, this fails due to a missing encoder. import enumeratum._ sealed trait Foo extends EnumEntry object Foo extends En...
Ultracentrifuge asked 2/4, 2019 at 22:39

3

How should I extract the value of a field of a case class from a given String value representing the field. For example: case class Person(name: String, age: Int) val a = Person("test",10) Now ...
Innkeeper asked 7/8, 2017 at 13:15

1

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I have defined a couple of case classes for JSON representation but I am not sure whether I did it properly as there a lot of nested case classes. Entities like spec, meta and so on are of type JSO...
Require asked 11/1, 2019 at 16:0

14

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Are there any best-practice guidelines on when to use case classes (or case objects) vs extending Enumeration in Scala? They seem to offer some of the same benefits.
Auriga asked 14/12, 2009 at 4:33

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