fixed warning on ruby 1.9.3
fixed warning on ruby 1.9.3

jasonm23/pry,ngpestelos/pry,ooohiroyukiooo/pry,printercu/pry,tdg5/pry,scalixte-mdsol/pry,raeno/pry,scalixte-mdsol/pry,bronzdoc/pry,gfvcastro/pry,pvdb/pry,josue804/debunker,sideci-sample/sideci-sample-pry,jasnow/pry,geoffreylitt/pry,ooohiroyukiooo/pry,shockone/pry,gfvcastro/pry,85x14/pry,caporta/pry,85x14/pry,geoffreylitt/pry,jasonm23/pry,icebreaker/pry,raeno/pry,shockone/pry,85x14/pry,caporta/pry,nju520/pry,tdg5/pry,pvdb/pry,nju520/pry,jasnow/pry,icebreaker/pry,bronzdoc/pry,shockone/pry,scalixte-mdsol/pry,sferik/pry,caporta/pry,nju520/pry,richo/pry,raeno/pry,deivid-rodriguez/pry,jasnow/pry,jasonm23/pry,sferik/pry,ngpestelos/pry,josue804/debunker,tdg5/pry,ooohiroyukiooo/pry,printercu/pry