Why in scala we need to define class structure to create new object of the same class - 


class readhelper{} object readhelper {}  class mainapp{    val rhelp = readhelper//this line uneasy if omit class declaration of readhelper }

why in scala need define class structure create new object of same class?

actually don't.

class readhelper{}  class mainapp{   val rhelp: readhelper = new readhelper }

please pay attention in original case 

class readhelper {} object readhelper {}  class mainapp{   val rhelp: readhelper.type = readhelper }

or just

object readhelper {}  class mainapp{   val rhelp: readhelper.type = readhelper }

rhelp has different type.

object readhelper not object (aka instance in oop-languages) of class readhelper. it's called companion object of class. class-like structure (a singleton) existing besides class. in byte code find 2 classes readhelper (the class itself) , readhelper$ (companion object).

maybe should read more classes, objects, companion objects in scala.


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