Scala Predef unimport [duplicate]
Possible Duplicate:
How to unimport String “+” operator in Scala?
So things from Predef get automatically imported into scala programs. But how can I disable- unimport certain or开发者_开发百科 all imported functions from Predef? As an example if I don't like the '+' operator on String how to disable this functionality?
As mentioned in the linked answer, the method String#+(other: Any)
is added to the String class with compiler magic, rather than with an implicit conversion. As such, it isn't related to the automatic import of Predef._
.
The same applies to Int#+(x: String)
, and corresponding method on the other value types.
However, there is another String concatenation method that is added by an implicit conversion in Predef
. x + "2"
is treated as Predef.any2stringAdd(x).+("2")
. By explicitly importing Predef
on the first line of your file, you can rename unwanted members to _
, disabling them.
import Predef.{any2stringadd => _, _}
object Test {
object A
A + "20" // error: value + is not a member of object Test.A
}
I don't think that this works in Scala Scripts or in the REPL. There is also an unsupported option, -Yno-predef
, to turn of the automatic import globally.
Related: SI-1931
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