linux - bash - 声明文档

Question

如果你声明一个这样的数组

declare -a test

你可以像这样回显该值

i=2
echo ${test[i]}

或

i="1+1" 
echo ${test[i]}

为什么接受第二种形式？我需要一个复杂的答案，谢谢

Answer 1

参见man bash:

The subscript is treated as an arithmetic expression that must evaluate to a number.

够复杂吗？