ruby 正则表达式的含义

[abc]A single character of: a, b, or c[^abc]Any single character except: a, b, or c[a-z]Any single character in the range a-z[a-zA-Z]Any single character in the range a-z or A-Z^Start of line$End of line\AStart of string\zEnd of string

.Any single character\sAny whitespace character\SAny non-whitespace character\dAny digit\DAny non-digit\wAny word character (letter, number, underscore)\WAny non-word character\bAny word boundary

(...)Capture everything enclosed(a|b)a or ba?Zero or one of aa*Zero or more of aa+One or more of aa{3}Exactly 3 of aa{3,}3 or more of aa{3,6}Between 3 and 6 of a