I'm not sure if this is what chromatic suggested, but either one of these should do what you're looking for: 
unless ( defined caller ) {
  #code here
}

[download]
or 
sub do_me {
  #code to run here
}
do_me unless defined caller;

[download]
sub do_me or the block after unless won't be executed when used or required, but will be executed from the command line.

From perldoc caller:

Returns the context of the current subroutine call. In scalar context, returns the caller's package name if there is a caller, that is, if we're in a subroutine or eval or require, and the undefined value otherwise.

In reply to Re: testing in perl: main and caller by bmann
in thread testing in perl: main and caller by water

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