use Perl

• just off the top of my head (Score:1)

  by jhorwitz (4227)

  • end the script with a false value like "0;" -- that will prevent 'require' and 'use' from successfully loading it
  • write your own import handler that just throws an error
  • Re:just off the top of my head (Score:2)

    by geoff (2013)

    well, the idea is that require(), etc is ok and in fact required. the problem is that the mainline code in the script needs to be suppressed when calling require(). for instance:

    #!/usr/bin/perl
    
    print "I should only print when '$ perl script.pl' ;
    
    package Foo;
    
    # lots of stuff that is ok to be pulled in via 'require "script.pl"
    • Re:just off the top of my head (Score:1)

      by jhorwitz (4227)

      okay, now i see why this is painful. this will require some more gears to turn in my brain.
    • Re:just off the top of my head (Score:1)

      by jhorwitz (4227)

      well, now all i can think of is checking $ARGV[0] for the script name. simple, but certainly not elegant or bulletproof.
• perhaps... (Score:2)

  by jmm (276)

  off the top of my head, no warrantee, YMMV, IANAL,... ... my $imported = 0; sub import { ... ++$imported; ... } END { unless( $imported ) { # script code goes here } }
  • Re:perhaps... (Score:2)

    by jmm (276)

    Drat, it looked fine when I previewed it, but the ECODE got lost somehow. Trying again:

    ...
    
    my $imported = 0;
    
    sub import {
        ...
        ++$imported;
        ...
    }
    
    ...
    
    END {
        unless( $imported ) {
            # script code goes here
        }
    }
• Will caller() do what you need? (Score:1)

  by wnodom (2030)

  Try this:
  
#! /usr/bin/perl -w
#
# script.pl
#

if (scalar caller)
    {
        print "Called via a sub, eval, or require.\n";
    }
else
    {
        print "Called directly.\n";
    }

print "Within script.pl\n";


  You could get fancier with caller() if you need to, but I think this will do the trick.
  
  There's more info in this recent journal entry by brian [perl.org].
  
  --Bill
  • Re:Will caller() do what you need? (Score:1)

    by chromatic (983)

    Yep; that's exactly the trick in Pod::ToDemo [cpan.org].