perl范围声明our,my,local

perl中的三个范围声明 our,my,local

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    <span style="font-size: x-small;">How are you doing?</span>
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    <span style="font-size: x-small;">&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8211;</span>
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    <span style="font-size: x-small;">跟用 my 时不一样了吧? 此时在greeting1调用greeting2时，greeting2可以看到greeting1的局部变量$hello,外部的全局变量当然就隐藏了。</span>
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