I don't remember where I learned the !~
method of the String
class. However I know it compares a string to a regex and check whether the string not match the regex. See my below example.
C:\>irb
irb(main):001:0> "abba" =~ /(\w)(\w)\2\1/i
=> 0
irb(main):002:0> "xxxx" =~ /(\w)(\w)\2\1/i
=> 0
irb(main):003:0> "asdf" =~ /(\w)(\w)\2\1/i
=> nil
irb(main):004:0> "asdf" !~ /(\w)(\w)\2\1/i
=> true
irb(main):005:0> "asdf" !~ /asdf/i
=> false
irb(main):006:0>
I want to find more information of the method but I can't find it in the rdoc of both String
and Regexp
. Anyone can give some help?
Thanks.
来源:https://stackoverflow.com/questions/14001250/ruby-regular-expression-method