lexical variable

基本解释

Similarly, after package B, $x=20 modifies the lexical variable, and not any of the package variables.
类似的，在package B后，$x=20修改了词法变量，而不是任何包变量。
Functions can refer to any variable in their lexical scope (the nested braces surrounding the function's definition), such as the local variables of a function that defines them.
函数可以引用词法作用域（包围函数定义的嵌套括号）内的任何变量，例如本地变量（由函数定义）。
It doesn't see the AAA because the variable with that value is a lexical variable, and only exists inside of A.
它不会见到AAA值，因为那个变量是个词法变量，仅仅存在于A里。