Ruby ;.,:'"{}[]()?!@#$%^&*-+=|\/ comments strings keywords numbers symbols identifiers Comments String \# $ \" [^\"]* \" \"\" \\ \\\" $ [a-z_A-Z][a-z_A-Z0-9]* '__FILE__' '__LINE__' 'alias' 'and' 'begin' 'break' 'case' 'class' 'def' 'defined?' 'do' 'else' 'elsif' 'end' 'ensure' 'false' 'for' 'if' 'in' 'keys' 'module' 'next' 'nil' 'not' 'or' 'redo' 'rescue' 'retry' 'return' 'self' 'super' 'then' 'true' 'undef' 'unless' 'until' 'when' 'while' 'yield' [.{}\[\]()!@%^*-+=<>:] [0-9][0-9]* 0x[0-9A-F]+ [1-9][0-9]*\.[0-9]* [1-9][0-9]*{\.[0-9]+}|e{[\+\-]}|[0-9]+