The code ':-' appears in three different locations apparently unrelated to parameter expansion in the 'cd_db' CD project which concludes Chapter 2.

1. function: set_menu_choice()

    echo "Options :-"

2. function: update_cd()

    echo "Current tracks are :-"

3. function: list_tracks()

    echo "$cdtitle :-"

Since in these three locations ':-' does NOT occur in the context of parameter expansion (as discussed on p 71, e.g., ${param:-default}), I don't see what ':-' adds here ... except for confusion.

Jim Keenan


Just Another Perl Hacker

I believe they are being used as part of the text you should see.
for example the line
echo "Options :-" will echo all characters in quotes, so you will see

Options :-

it is just text, not a parameter expansion.

good day