Here are some simple Unix and Windows one-liners that check whether a module is installed. They return 1 or 0 accordingly: 
    (Unix) perl -le 'print 0 + eval "require $ARGV[0]"'   Some::Module

    (Win)  perl -le "print 0 + eval qq(require $ARGV[0])" Some::Module

[download]

Or as a program with clearer output: 

    #!/usr/bin/perl -wl

    for my $module (@ARGV) {
        print "$module is ", 
              eval "require $module" ? "" : "not ",
              "installed.";
    }

    __END__


    $ perl installed.pl Parse::RecDescent Parse::RecklessDescent

    Parse::RecDescent is installed.
    Parse::RecklessDescent is not installed.

[download]

--
John.

In reply to Re: Checking for modules by jmcnamara
in thread Checking for modules by Anonymous Monk

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