- Notes on Perl
- Notes on Perl on Windows
- Notes on Perl modules we use
- Notes on installing a perl module
Notes on Perl
For our scripts, we rely quite a bit on Perl, and increasingly on
some core Perl modules. These Perl modules are part of the Perl
source, so if you build Perl on your own, you should be set.
However, if you install Perl as binary packages, the outcome might
differ, and you may have to check that you do get the core modules
installed properly. We do not claim to know them all, but experience
has told us the following:
- on Linux distributions based on Debian, the package 'perl' will
install the core Perl modules as well, so you will be fine.
- on Linux distributions based on RPMs, you will need to install
'perl-core' rather than just 'perl'.
You MUST have at least Perl version 5.10.0 installed. This minimum
requirement is due to our use of regexp backslash sequence \R among
other features that didn't exist in core Perl before that version.
Notes on Perl on Windows
There are a number of build targets that can be viewed as "Windows".
Indeed, there are VC-* configs targeting VisualStudio C, as well as
MinGW and Cygwin. The key recommendation is to use "matching" Perl,
one that matches build environment. For example, if you will build
on Cygwin be sure to use the Cygwin package manager to install Perl.
For MSYS builds use the MSYS provided Perl. For VC-* builds we
recommend ActiveState Perl, available from
Notes on Perl on VMS
You will need to install Perl separately. One way to do so is to
download the source from http://perl.org/, unpacking it, reading
README.vms and follow the instructions. Another way is to download a
.PCSI file from http://www.vmsperl.com/ and install it using the
POLYCENTER install tool.
Notes on Perl modules we use
We make increasing use of Perl modules, and do our best to limit
ourselves to core Perl modules to keep the requirements down. There
are just a few exceptions:
Test::More We require the minimum version to be 0.96, which
appeared in Perl 5.13.4, because that version was
the first to have all the features we're using.
This module is required for testing only! If you
don't plan on running the tests, you don't need to
bother with this one.
Text::Template This module is not part of the core Perl modules.
As a matter of fact, the core Perl modules do not
include any templating module to date.
This module is absolutely needed, configuration
depends on it.
To avoid unnecessary initial hurdles, we have bundled a copy of the
following modules in our source. They will work as fallbacks if
these modules aren't already installed on the system.
Notes on installing a perl module
There are a number of ways to install a perl module. In all
descriptions below, Text::Template will serve as an example.
1. for Linux users, the easiest is to install with the use of your
favorite package manager. Usually, all you need to do is search
for the module name and to install the package that comes up.
On Debian based Linux distributions, it would go like this:
$ apt-cache search Text::Template
libtext-template-perl - perl module to process text templates
$ sudo apt-get install libtext-template-perl
Perl modules in Debian based distributions use package names like
the name of the module in question, with "lib" prepended and
2. Install using CPAN. This is very easy, but usually requires root
$ cpan -i Text::Template
Note that this runs all the tests that the module to be installed
comes with. This is usually a smooth operation, but there are
platforms where a failure is indicated even though the actual tests
were successful. Should that happen, you can force an
installation regardless (that should be safe since you've already
seen the tests succeed!):
$ cpan -f -i Text::Template
Note: on VMS, you must quote any argument that contains uppercase
characters, so the lines above would be:
$ cpan -i "Text::Template"
$ cpan -f -i "Text::Template"