```package mcaa.wechat import org.junit.Test /**...

# getting-started

[feng-zihao]

package mcaa.wechat

import org.junit.Test

/**
 * Created by fengzh on 9/13/16.
 */
class Playground {

    fun foo(): String? {
        val x = null as String?
        return x
    }

    @Test fun test() {
        println(foo())
    }
}