为什么在AppleScript的，你能不能申报变量的引用局部处理程序？ [英] Why, in AppleScript, can't you declare references to variables local to handlers?
问题描述
你为什么不能声明，除非引用的变量是全球范围内的使用变量的引用？请解释运行时内存或对象结构，导致了下列现象：
Why can't you declare and use references to variables unless the variable referenced is scoped globally? Please explain the runtime memory or object structure that leads to the following phenomenon:
脚本A失败：
on foo()
set l to {0}
set lref to a reference to l
return item 1 of lref
end foo
foo()
脚本B成功：
on run
set l to {0}
set lref to a reference to l
return item 1 of lref
end run
脚本C成功：
on foo()
global l
set l to {0}
set lref to a reference to l
return item 1 of lref
end foo
foo()
参见：<一href=\"http://stackoverflow.com/questions/15753161/how-do-you-efficiently-build-a-list-within-a-handler-in-applescript/15754609#15754609\">How你有效地AppleScript的一个处理程序中建立一个列表？和<一个href=\"http://stackoverflow.com/questions/3569847/why-cant-applescript-make-firstvalue-of-hash-into-type-reference-in-this-test-c?rq=1\">Why不能做的AppleScript哈希firstValue到本次测试code型参考？
推荐答案
由于参考是同样的事情作为对象说明，所以你不能做的东西的参考，是不是（或者由包含东西是不是）一个对象就AppleScript的关注。
Because a "reference" is the same thing as an object specifier, so you can’t make a reference to something that isn’t (or is contained by something that isn’t) an object as far as AppleScript is concerned.
一个全局变量是由顶级脚本对象所拥有的 - 它真的没有初始化的属性。 （您也可以到脚本属性的引用;它不具有严格全局）
A global variable is owned by the top-level script object -- it’s really a property with no initializer. (You can also have a reference to a script property; it doesn’t have to be strictly global.)
一个局部变量，另一方面，由处理程序，它是在呼叫帧拥有，并调用帧不在AppleScript的对象，因此，没有引用
A local variable, on the other hand, is owned by the call frame of the handler that it’s in, and call frames are not objects in AppleScript, therefore, no references.
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