convert gem list to gem install reference: https://www.krzywanski.net/archives/451

gems_install_list.pl

#!/usr/bin/perl -w

# We're strict
use strict;

# Get list of installed gems
my @gems = qx(gem list);
chomp(@gems);

# Create commands
foreach my $gem (@gems)
{
	# Match gem and versions
	$gem =~ m/(\S+)\s\((.+)\)/i;
	# Gem name
	$gem = $1;
	# Save them into array	
	my @gem_versions = split(/,/, $2);
	# Print out commands
	foreach (@gem_versions)
	{
		# Remove all whitespaces
		$_ =~ s/^\s+//;
		print "gem install $gem --version=$_\n";
	}
}