; ()   - grouping
; []   - optional parts
; *    - repetition zero or more times
; +    - repetition once or more times
; none - sequence
; |    - alternatives
; -{<} - All characters except '<'


 PHONELOG	: "<PHONELOG" ["version" "=" digits ["revision" "=" digits]] ">"
                  (ENTRY | MARK)*
                  ["</PHONELOG>"]

 ENTRY		: "<ENTRY>" [PROGRAM] HOST ((START END [PERIOD]) | BUSY | NOANSWER) "</ENTRY>"

 HOST		: "<HOST>" NUMBER [HOSTNAME] [REASON] "</HOST>"
 NUMBER		: "<NUMBER>" text "</NUMBER>"
 HOSTNAME	: "<HOSTNAME>" text "</HOSTNAME>"
 REASON		: "<REASON>" text "</REASON>"

 BUSY		: "<BUSY>" DATE TIME "</BUSY>"
 NOANSWER	: "<NOANSWER>" DATE TIME "</NOANSWER>"

 START		: "<START>" DATE TIME "</START>"
 END		: "<END>" [DATE] TIME "</END>"
 DATE		: "<DATE>" year "-" month "-" day "</DATE>"
 TIME		: "<TIME>" hour ":" min ":" sec "</TIME>"
 PERIOD		: "<PERIOD>" [hours "H"] [mins "M"] [secs "S"] "</PERIOD>"

 MARK		: "<MARK>" PROGRAM MARKNAME "</MARK>"
 MARKNAME	: "<MARKNAME>" text "</MARKNAME>"

 PROGRAM	: "<PROGRAM" ["version" "=" digits ["revision" "=" digits]] ">"
                  text
                  "</PROGRAM>"

 year		: [[[digit] digit] digit] digit
 month		: [0-1] digit
 day		: [0-3] digit
 hour		: [0-2] digit
 min		: [0-5] digit
 sec		: [0-5] digit
 hours		: digit+
 mins		: [0-5] digit
 secs		: [0-5] digit

 digits         : digit+
 digit          : 0-9
 text           : (-{<})*