anchor.diff:  statement
      : expression2 ';'
      | cond
  -   | while
  -   | do_while
  -   | for
  -   | switch
  -   | case
  -   | default
  +   | while_stmt
  +   | do_while_stmt
  +   | for_stmt
  +   | switch_stmt
  +   | case_stmt
  +   | default_stmt
      | block
  -   | foreach
  -   | break
  -   | continue
  +   | foreach_stmt
  +   | break_stmt
  +   | continue_stmt
      | ';'
      ;
   
  
positive.code:    : IDENTIFIER ('.' IDENTIFIER)*
     ;
  
  call
     : expression6 '(' expression_list ')'
     ;
  
  index
     : expression6 '[' expression ('..' expression)? ']'
     ;
  
  array
     : '({' expression_list '})'
  
negative.code:    : '([' (expression ':' expression (',' expression ':' expression)*)? ','? '])'
     ;
  
  
  program_specifier
     :
  