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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