Bash中变量变量的变化(Variation on a Variable Variable in Bash)

Bash中变量变量的变化(Variation on a Variable Variable in Bash)

我正在寻找一种方法来将字符串添加到bash中的变量名称并将其作为新变量进行评估。 例：

#!/bin/bash file="filename" declare ${file}_info="about a file" declare ${file}_status="status of file" declare ${file}_number="29083451" echo ${${file}_info} # <-- This fails with error: "bad substitution"

有没有办法做到这一点？

我实际上并没有在任何地方的任何生产代码中实现它 。 我只想知道是否有某种方法可以使用变量和字符串创建变量名称。 这似乎是一个有趣的问题。

另请注意，我不是在询问bash间接，这是使用${!x}来将变量的内容作为变量进行评估。

I am looking for a way to add a string to a variable name in bash and evaluate this as a new variable. Example:

#!/bin/bash file="filename" declare ${file}_info="about a file" declare ${file}_status="status of file" declare ${file}_number="29083451" echo ${${file}_info} # <-- This fails with error: "bad substitution"

Is there a way to do this?

I'm not actually implementing this in any production code anywhere. I just want to know if there is some way to create a variable name using a variable and a string. It seemed like an interesting problem.

Also note that I am not asking about bash indirection, which is the use of ${!x} to evaluate the contents of a variable as a variable.

最满意答案

你不是在询问间接问题，但这可以帮助你：

info=$file\_info echo ${!info}

You aren't asking about indirection, but that's what can help you:

info=$file\_info echo ${!info}