Passing arguments by reference

Question

I want to ask if it is possible to pass arguments to a script function by reference:

i.e. to do something that would look like this in C++:

Answer 1

Eval should never be used on a string that a user can set because its dangerous. Something like "string; rm -rf ~" will be bad. So generally its best to find solutions where you don't have to worry about it.

However, eval will be needed to set the passed variables, as the comment noted.

$ y=four
$ four=4
$ echo ${!y}
4
$ foo() { x=$1; echo ${!x}; }
$ foo four
4