[sf-perl] use lib: order doesn't seem to matter

[Michael Friedman]

David,

I managed a work around for this behavior at my office a while ago. We have each developer set an environment variable containing their personal module path and use that in preference to the default. It requires this at the top of each script, though:

BEGIN {
    if ( $ENV{PERL_LIB} =~ /\:/ ) {
        unshift( @INC, split( /\:/, $ENV{PERL_LIB} ) );
    }
    elsif ( $ENV{PERL_LIB} ) {
        unshift( @INC, $ENV{PERL_LIB} );
    }
    else {
        unshift( @INC, '/path/to/production/lib/perl5' );
    }
}


The colon splitting was added when we realized we wanted to split our perl modules into multiple CVS projects. They're all in one production directory, but in individual project directories for each developer.

-- Mike
______________________________________________________________________________
Mike Friedman | HighWire Press, Stanford Univ | friedman at highwire.stanford.edu

On Aug 24, 2010, at 10:53 AM, David Alban wrote:

> greetings,
> 
> one of our customary 'use lib' statements for a local program is:
> 
>  use lib '/nas/reg/lib/perl';
> 
> i'm modifying the program and in my development area, i want to use a
> locally modified version of one of the modules it uses.
> 
> but it's picking up the installed module rather than my local module.
> 
> here's what i'm seeing:
> 
>  DB<1> l 1+10
> 1       #!/usr/bin/perl
> 2
> 3:      use strict;
> 4:      use warnings;
> 5
> 6:      use lib '/nas/reg/lib/perl';
> 7
> 8            ##### => dbg
> 9:      use lib
> '/nas/home/dalban/perforce/srwd00reg001/default/internal/reg/pb_reg_nasify_properties/lib/perl';
> 10           ##### <= dbg
> 11
>  DB<2> x @INC
> 0  '/nas/reg/lib/perl/x86_64-linux-thread-multi'
> 1  '/nas/reg/lib/perl/5.8.5'
> 2  '/nas/reg/lib/perl'
> 3  '/nas/home/dalban/perforce/srwd00reg001/default/internal/reg/pb_reg_nasify_properties/lib/perl'
> 
> and if i reverse the order in which i "use" them, i get:
> 
>  DB<1> l 1+10
> 1       #!/usr/bin/perl
> 2
> 3:      use strict;
> 4:      use warnings;
> 5
> 6            ##### => dbg
> 7:      use lib
> '/nas/home/dalban/perforce/srwd00reg001/default/internal/reg/pb_reg_nasify_properties/lib/perl';
> 8            ##### <= dbg
> 9
> 10:     use lib '/nas/reg/lib/perl';
> 11
>  DB<2> x @INC
> 0  '/nas/reg/lib/perl/x86_64-linux-thread-multi'
> 1  '/nas/reg/lib/perl/5.8.5'
> 2  '/nas/reg/lib/perl'
> 3  '/nas/home/dalban/perforce/srwd00reg001/default/internal/reg/pb_reg_nasify_properties/lib/perl'
> 
> i thought 'use lib' had the effect of unshifting its arg onto @INC,
> but /nas/reg/lib/perl seems to "win" no matter in what order i specify
> the libs.
> 
> i've done this before with no problem.  i'm sure i'm missing
> something.  or perhaps it only seemed to work before...
> 
> what am i missing?
> 
> thanks,
> david
> -- 
> Live in a world of your own, but always welcome visitors.
> _______________________________________________
> SanFrancisco-pm mailing list
> SanFrancisco-pm at pm.org
> http://mail.pm.org/mailman/listinfo/sanfrancisco-pm