问题
How do I import a package into Scala's REPL?
I am trying to import this package called funsets which has an object named "FunSets".
I tried several variations of import funsets._ and import funsets._; etc but it is still not importing the functions and object in the package.
回答1:
One way is to compile the "scala classes" and put those in classpath.
Example,
1) Say you have a class funsets.FunSets.scala
package funsets
object FunSets {
def fun = "very fun"
}
2) Compile the class first using scalac. (If you use sbt then sbt compile would put compiled classes in target/ folder)
scalac FunSets.scala
You will see the funsets folder/package created,
$ ls -l
total 16
-rw-r--r-- 1 updupd NA\Domain Users 63 Dec 18 11:05 FunSets.scala
drwxr-xr-x 4 updupd NA\Domain Users 136 Dec 18 11:06 funsets
3) Then start REPL with funsets package in classpath
$ scala -classpath .
Welcome to Scala 2.12.3 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_151).
Type in expressions for evaluation. Or try :help.
scala> import funsets._
import funsets._
Note: if you use sbt compile, put target/classes in classpath.
Access Funsets singleton,
scala> FunSets.fun
res0: String = very fun
Also read Scala REPL unable to import packge
回答2:
You need to add the appropriate jar(s) to the classpath as well using the -cp <jar files> argument when starting the repl. Alternatively you can use the :require <jar file> directive from the repl to load a jar after you've already started the session.
回答3:
Assuming you have some code in a scala file, you can load external scala files from the scala repl using the :load command. More info in this answer.
来源：https://stackoverflow.com/questions/47874731/how-to-import-package-into-scala-repl