Roots, dirs and files.

• $dir
  • Something you can open and you can do a file test on.
  • C:/www/domain/docroot/articles/2008/08/10
• $file
  • Something you can open and you can do a file test on.
  • C:/www/domain/docroot/articles/2008/08/10/01.html
• $dirname
  • 10
  • But could also be 2008/08/10
• $filename
  • Including any extension
  • 01.html
• $path
  • Banned.
  • Ambiguous and half the time not what I expect and almost certainly not what I expected yesterday :-)
• $xxx_root
  • Key, often used dirs in a “web space”

An instance script might set

$web_root C:/www
$domain_root domain
[download]

A config file might have

docroot docroot
art_root articles
pic_root pics
[download]

A base class could have helper methods/assessors for each of the “roots”

Sub docroot{
  my  $self = shift;
  my $cnf = $self->cnf;
  return join(
    q{/},
    $cnf->param(q{$web_root}),
    $cnf->param(q{$domain_root}),
    $cnf->param(q{docroot}),
  );
}

sub art_root {
  my $self = shift;
  my $cnf = $self->cnf;
  return join(
    q{/},
    $self->docroot,
    $cnf->param(q{art_root}
  );
}
[download]

A dir, is a xxx_root, and possibly one or more dir names. A file is a dir with a file name on the end.

my $article_file = join(
  q{/},
  $self->art_root,
  $art_dirname,
  $art_filename,
);
[download]

Anything that needs to be in an html page is $href and $src etc.

What’s wrong with path? Take a selection of core modules:

File::Basename - Parse file paths into directory, filename and suffix.
File::Path - create or remove directory trees
File::Spec - portably perform operations on file names

I find it confusing to keep on top of what a path is in the different contexts. Throw base and suffix into the mix and I’m rereading the docs again for the umpteenth time. File::Spec’s abs2rel talks about $base and $path. And where did those trees come from? And what do you do with a suffix list?

I would use these modules more if I didn’t get into such a tangle. I invariably have helper methods with names that better fit the conventions I’ve outlined e.g. mkdir.

While far from perfect everything has been a lot smoother since banning path.

A plague on paths!

How do monks manage to avoid such confusion?

update: fixed the join syntax
update2: fixed the links