one_liner_for_gem_install

# sample list gem_list file

beanstalk-client (1.0.2)
bluecloth (2.0.5)
builder (2.1.2)
capistrano (2.5.13)
capistrano-ext (1.2.1)
capistrano_s3 (0.1.1)
cgi_multipart_eof_fix (2.5.0)
columnize (0.3.1)
daemons (1.0.10)
eventmachine (0.12.10)
facter (1.5.7)
fakeweb (1.2.8)
fastthread (1.0.7)
fcgi (0.8.8)
ferret (0.11.6)


# one liner for gem installation

cat gem_list.txt | python -c "import sys;import re; from itertools import chain; l=sys.stdin.readlines();x=[ [ ' install --no-ri --no-rdoc ' + line[:-1][:line.index(' ')] + ' --version ' +k for k in line[line.index('(')+1:line.index(')')].split(',')]   for line in l]; print '\n'.join(item for item in chain(*x))" | xargs -L 1 -t gem