From 8ddf2e94df70707b458528a437759b96046d3e01 Mon Sep 17 00:00:00 2001 From: Franck Cuny Date: Tue, 26 Nov 2013 10:36:10 -0800 Subject: Huge update. Moved all posts from textile to markdown. Updated all the CSS and styles. Added a new page for the resume. --- ...es-i-like-getopt-long-and-moosex-getopt.textile | 133 --------------------- 1 file changed, 133 deletions(-) delete mode 100644 _posts/2009-06-22-modules-i-like-getopt-long-and-moosex-getopt.textile (limited to '_posts/2009-06-22-modules-i-like-getopt-long-and-moosex-getopt.textile') diff --git a/_posts/2009-06-22-modules-i-like-getopt-long-and-moosex-getopt.textile b/_posts/2009-06-22-modules-i-like-getopt-long-and-moosex-getopt.textile deleted file mode 100644 index 4f9470d..0000000 --- a/_posts/2009-06-22-modules-i-like-getopt-long-and-moosex-getopt.textile +++ /dev/null @@ -1,133 +0,0 @@ ---- -layout: post -category: perl -title: Modules I like Getopt::Long and MooseX::Getopt ---- - -h3. Getopt::Long - -"Getopt::long":http://search.cpan.org/perldoc?Getopt::Long is a useful module to parse command line arguements. - -A basic usage is something like this: - -{% highlight perl %} -#!/usr/bin/perl -w -use strict; -use YAML::Syck; -use Getopt::Long; - -GetOptions('config=s' => \my $cfg_file,); - -my $config = LoadFile $cfg_file -{% endhighlight %} - -In *GetOptions*, we require a value for config with *config=s*. If we wante an integer, we replace 's' with 'i', and for a floating point, with 'f'. - -Call your script : - -{% highlight bash %} - script.pl --config=file.yml #this one works - script.pl --config file.yml #this one too! - script.pl -c file.yml #and this one too -{% endhighlight %} - -The three syntaxes are understood. - -A good practices is to combine this module with "Pod::Usage":http://search.cpan.org/perldoc?Pod::Usage. Let's do some modifications on the example: - -{% highlight perl %} -#!/usr/bin/perl -w -use strict; -use YAML::Syck; -use Getopt::Long; -use Pod::Usage; - -GetOptions('config=s' => \my $cfg_file,) or pod2usage(2); -pod2usage(2) unless @ARGV > 0; - -my $config = LoadFile $cfg_file - -__END__ -=head1 NAME - -uberscript - -=head1 SYNOPSIS - -uberscript [options] - -Options: - - --config config file - -=head1 Options - -=over 4 - -=item B - -Path to the config file -{% endhighlight %} - -then - -{% highlight bash %} -$ perl uberscript - -Usage: - uberscript [options] - - Options: - --config config file -{% endhighlight %} - -From now if we call our script without argument, the POD will be printed on STDIN. - -h3. MooseX::Getopt - -"MooseX::Getopt":http://search.cpan.org/perldoc?MooseX::Getopt) is a Role that add a new_with_options to your object. We create a basic Object : - -{% highlight perl %} -package OurShinyObject; - -use Moose; -with qw/MooseX::Getopt/; - -has 'config' => (isa => 'Str', is => 'ro', required => 1); -has 'context' => ( - isa => 'HashRef', - is => 'rw', - lazy => 1, - traits => ['NoGetopt'], - default => sub { LoadFile shift->config } -); - -... -{% endhighlight %} - -create a script to call this object - -{% highlight perl %} -#!/usr/bin/perl -w -use strict; -use OurShinyObject; - -my $obj = OurShinyObject->new_from_options(); - -{% endhighlight %} - -bc. script.pl --config file.yml - -The role will set our attribute **context** using the value from the argument set on the command line. - -The - -{% highlight perl %} -traits => ['NoGetopt'] -{% endhighlight %} - -indicate that this attributes will be not be read from the command line. An alternate way to do this is to prefix the attributes with *_*. - -h3. conclusion (?) - -When you write a script, even if you're sure you will never need to have more than one argument, or that you never will have to update the code, *please* consider to use of *Getopt::Long* instead of a *shift @ARGV*, because we all know that you will at a certain point update this script and you will more than one argument :). -- cgit v1.2.3