In ruby, I read some of the operators, but I couldn't find
regexs = (/\d+/)
a = somestring
if a =~ regexs
=~ operator matches the regular expression against a string, and it returns either the offset of the match from the string if it is found, otherwise nil.
ruby-1.9.2-p136 :003 > /mi/ =~ "hi mike" => 3 ruby-1.9.2-p136 :004 > "hi mike" =~ /mi/ => 3 ruby-1.9.2-p136 :005 > "mike" =~ /ruby/ => nil
You can place the string/regex on either side of the operator as you can see above.