bash - Unable to add escape sequences dynamically for 'PS1'

Question

Say I want to include an escape sequence dynamically:

if [ -n $something ]; then
    user="u"
else
    user="admin"
fi
PS1='$user@h$ '

The problem is, instead of filling in the user name, my prompt looks like this:

u@ubuntu-1$ 

Even if I escape the backslash (user="\u") it still does not print out the user name. How do I get the prompt to look like this:

andreas@ubuntu-1$ 

Answer 1

Use double quotes when you are trying to interpolate variables and want them to expand.

You also have another option, instead of dealing with u and complications with when the interpretation of it happens.

if [ -n $something ]; then
    user=`whoami`
else
    user="admin"
fi
PS1="$user@h$ "