小编sum*_*ion的帖子

我正在尝试解析一个命令和一个int来在板上做一个"乌龟"移动.我有点不知所措,因为它没有抛出异常,我甚至无法弄清楚如何在没有它的情况下打开调试器.

我的代码:

"only should begin parsing on new line"
endsWithNewLine:= aTurtleProgram endsWith: String cr.
endsWithNewLine ifTrue:[
    "splits commands based on new lines"
    commands := aTurtleProgram splitOn: String cr.
    commands do:[:com |
        "should split into command and value for command"
        i := com splitOn: ' '.
        "command"
        bo := ci at: 1.
        val := ci at: 2.
        "value for command"
        valInt := val asInteger.
        ^ bo = 'down' "attempted switch"
            ifTrue: [ turtle down: valInt ]
            ifFalse: [
              bo = 'left' …