Why is Scala's behavior in case of overloading with by-name parameters different from the case with by-value parameters? -


given scala code:

object test {    def byval(a: int) = println("int")   def byval(a: long) = println("long")    def byname(a: => int) = println("=> int")   def byname(a: => long) = println("=> long")    def main(args: array[string]) {       byval(5)       byname(5)   } }

the call byval(5) compiles correctly, byname fails compile:

ambiguous reference overloaded definition

why? expect observe same behavior by-value , by-name parameters respect overloading… how can fixed?

that's because jvm not support "by-name" parameter, scala has implement in way. => x compiles function0[x], erases function0[object], makes impossible scala distinguish 2 methods differ expected type of by-name parameter.


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