In bash, how can I echo the variable name, not the variable value? [closed]

Question

Suppose that I have a variable var in bash. I can assign a value to it. For example, I will make it a string:

var="Test"

I want to echo the name of var, not the value held by var. (I can do the latter with echo $var, but I actually want to do the former.)

The answer to this question from SO says to use echo ${!var}, but when I do that I echo just returns a blank line. For example, this bash script

#!/bin/bash

echo "Hi"
var="Test"
echo ${!var}
echo "Bye"

returns this output:

Hi

Bye

with just a blank line between Hi and Bye, instead of var. What am I doing wrong?

I'm running bash 4.1.5(1) on Ubuntu 10.04.4.

Answer 1

The shell parameter expansion ${!name@} or ${!name*} could do the trick,

$ foo=bar
$ var_name=(${!foo@})
$ echo $var_name" = "$foo
foo = bar

Although feasible I can't imagine the utility of this ...

Answer 2

If you want to simply output a static variable name, you can escape the $-sign:

echo \$var