String#split is a pretty-well known and commonly used method. Still, its behaviour in some cases might surprise you: irb(main):001:0> 'foo.bar'.split('.') => ["foo", "bar"] irb(main):002:0> '...'.split('.') => [] irb(main):003:0> 'foo...'.split('.') => ["foo"] irb(main):004:0> 'foo'.split('.') => ["foo"] irb(main):005:0> ''.split('.') => [] No comment needed. Keep Ruby weird!
