Check if module is installed

DreamT has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Check if module is installed by keszler (Priest) on Nov 16, 2009 at 10:38 UTC
perldoc -f require : no option for checking the version on a module like with use. I hate to ask a stupid question, but when troubleshooting I always start at the "is it plugged in" basics: Is Mail::Sendmail installed?	[reply]
Re^2: Check if module is installed by DreamT (Pilgrim) on Nov 16, 2009 at 11:08 UTC
Ok! No, It's not installed, the purpose was to create some "try/catch" code to catch the error if the module isn't installed, since the code is to be distributed to several machines.	[reply]
Re^3: Check if module is installed by DrHyde (Prior) on Nov 16, 2009 at 11:32 UTC
You want string eval: `eval "use Some::Module 94.5"; if($@) { print "Oh noes, it's not installed!\n"; } else { ... }` [download]	[reply] [d/l]
Re^4: Check if module is installed by JavaFan (Canon) on Nov 16, 2009 at 11:46 UTC
Re^5: Check if module is installed by DrHyde (Prior) on Nov 17, 2009 at 10:36 UTC
Re: Check if module is installed by biohisham (Priest) on Nov 16, 2009 at 10:51 UTC
I use an array that holds the required modules and then evaluate $@, sometimes evaluating a module's existence is nice if you are sharing your code across machines `@module = ("require Mail::Sendmail 0.75"); for(@module){ eval; if($@){ $_=~/\w+\W(\S+)/; print "Module $1 does not exist, please install it fir +st!\n"; }else{ #do stuff } };` [download] Excellence is an Endeavor of Persistence. Chance Favors a Prepared Mind.	[reply] [d/l] [select]
Re: Check if module is installed by Fox (Pilgrim) on Nov 16, 2009 at 14:47 UTC
how about use perl `$module = "bigfloat"; qx(perl -M$module -e 'exit' 2>/dev/null); print "$module is not installed !!\n" if $? != 0;` [download]	[reply] [d/l]
Re: Check if module is installed by bichonfrise74 (Vicar) on Nov 16, 2009 at 19:01 UTC
I wonder if you can use something like this? `#!/usr/bin/perl use strict; use ExtUtils::Installed; my $check_mod = ExtUtils::Installed->new(); die "File::Find is not installed" unless ( grep /File::Find/, $check_mod->modules() );` [download]	[reply] [d/l]
Re: Check if module is installed by bart (Canon) on Nov 16, 2009 at 13:57 UTC
I assume what you really want is to provide an option for the program can send mail in one of a few possible ways. Or, not at all, if it's not available. (Note that it's possible that you cannot send mail even though you have the necessary mail modules.) In that case, I'd write a little wrapper module that tries to load one of a few mail modules, writes down what module to use, and provides a hook to send mail using that module without exposing too much to the client program. Perhaps you can base that on a module like MIME::Lite, since that already has a way to transparently send mail using one of a few possible modules.	[reply]
Re: Check if module is installed by hecroce (Friar) on Nov 17, 2009 at 00:41 UTC
Hi, This is what i did for a similar case: use strict; use warnings; use ExtUtils::Installed; # # First, check if all the required modules have # been installed inthe system this script will run on. # BEGIN { my @import_modules = ( 'Getopt::Lucid', 'Apache::Htpasswd', 'IO::CaptureOutput' ); my ($inst) = ExtUtils::Installed->new(); my (@installed_modules) = $inst->modules(); for ( @import_modules ) { eval{ $inst->validate($_) }; if($@) { print qq{\n Module $_ does not seem to be installed in this system. Please install the module and try again!\n }; exit 1; } # end 'if' } # end 'for' } # end 'BEGIN' block [download]	[reply] [d/l]
use Module::Load::Conditional by gnosti (Chaplain) on Nov 17, 2009 at 22:55 UTC
One more possibility is to use an Module::Load::Conditional	[reply]


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