types - Found scala.Unit, required Unit -


i have simple container trait so:

trait handler {   def apply[in, out](in: in): out }

when try implement it:

new handler {   def apply[any, unit](in: any) = println(in) }

i error:

[error]  found   : scala.unit [error]  required: unit(in method apply) [error]       def apply[any, unit](in: any) = println(in)

why this? can fix compiler error?

there same question correct answer.

you use trait type parameter, not method type parameter:

trait handler[out] {   def apply[in](in: in): out }  new handler[unit] {   def apply[in](in: in) = println(in) }

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