warning: language version 2.0 is experimental, there are no backwards compatibility guarantees for new language and library features
compiler/testData/cli/jvm/firLightTree.kt:2:5: error: variable expected
    this += "Alpha"
    ^
compiler/testData/cli/jvm/firLightTree.kt:3:15: error: classifier 'class System : Any' does not have a companion object, and thus must be initialized here
    java.lang.System = null
              ^
compiler/testData/cli/jvm/firLightTree.kt:3:15: error: variable expected
    java.lang.System = null
              ^
compiler/testData/cli/jvm/firLightTree.kt:3:24: error: null can not be a value of a non-null type 'kotlin/Unit'
    java.lang.System = null
                       ^
COMPILATION_ERROR