anchor.diff:  
   fragment HEX_DIGIT: [0-9a-fA-F];
   
  -// bool
  -BOOLEAN_LITERAL: 'true' | 'false';
  -
  -SHEBANG
  -   : '#!' ~'\n' // TODO
  -   ;
  +//SHEBANG
  +//   : '#!' ~'\n' // TODO
  +//   ;
   
   LIFETIME_OR_LABEL: '\'' NON_KEYWORD_IDENTIFIER;
   
  -emmmm: EOF;
  +// entry point
  +crate: innerAttribute* item* EOF;
   
   identifierOrKeyword
      : // only ascii
  
positive.code: crateRef: identifier | 'self';
  asClause: 'as' (identifier | '_');
  
  useDeclaration: 'use' useTree;
  useTree
     : (simplePath? '::')? '*'
     | (simplePath? '::')? '{' ( useTree (',' useTree)* ','?)? '}'
  
negative.code:    ;
  
  function
     : functionQualifiers 'fn' identifier generics? '(' functionParameters? ')' functionReturnType? whereClause?
        blockExpression
     ;
  
  