The = command is used to create command aliases. If you find yourself issuing the same long command over and over again, you can create an alias for that command. For example, the debugger command
= pFoo print("foo=$foo\n");
creates an alias called pFoo.
After this command is issued, typing pFoo
at the debugger prompt produces the same results as typing
print("foo=$foo\n");.
You use the = command without any arguments when you want a list of the current aliases.
If you want to set up some aliases that will always be defined, create a file called .perldb and fill it with your alias definitions. Use the following line as a template:
$DB::alias{'pFoo'} = 'print("foo=$foo\n");';
After you create this file and its alias definitions, the aliases will be available in every debugging session.