Telephone Number Parser

grammar telephone;

start: '+1'? '+'? variation
   ;

variation
   : nanp
   | japan
   | airtel
   | gp
   | robi
   | bl
   ;

// North American Numbering Plan
nanp
   : '011' areacode exchange subscriber
   ;

// Airtel Numbering Plan
airtel
   : '016' areacode exchange subscriber
   ;

//Grameenphone Numbering Plan
gp
   : '017' areacode exchange subscriber
   ;

//Robi Numbering Plan
robi
   : '018' areacode exchange subscriber
   ;

//Banglalink Numbering Plan
bl
   : '019' areacode exchange subscriber
   ;

areacode
   : DIGIT DIGIT DIGIT
   ;

// Exhange
exchange
   : DIGIT DIGIT DIGIT
   ;

// Subscriber
subscriber
   : DIGIT DIGIT DIGIT DIGIT
   ;

// Japan
japan
   : '010' areacode exchange subscriber
   ;

DIGIT
   : [0-9]
   ;

WS
   : [ \r\n] + -> skip
   ;