Abstract Syntax

003  'type' DECL 
004     dcl(IDENT, DEF, POS) 
  
005  'type' DECLLIST 
006     decllist(DECL, DECLLIST) 
007     nil 
  
008  'type' DEF 
009     variable(TYPE) 
010     valueparam(TYPE) 
011     varparam(TYPE) 
012     proc(Formals: DECLLIST, Locals: DECLLIST, STMT) 
  
013  'type' TYPE 
014     integer 
015     real 
016     boolean 
017     array(INT, INT, TYPE) 
018     none 
  
019  'type' STMT 
020     assign(DESIG, EXPR, POS) 
021     read(DESIG, POS) 
022     write(EXPR, POS) 
023     call(IDENT, EXPRLIST, POS) 
024     if(EXPR, STMT, STMT, POS) 
025     while(EXPR, STMT, POS) 
026     seq(STMT, STMT) 
  
027  'type' DESIG 
028     id(IDENT, POS) 
029     subscr(DESIG, EXPR, POS) 
030     none 
  
031  'type' EXPR 
032     binary(OP, EXPR, EXPR, POS) 
033     opnot(EXPR, POS) 
034     int(INT) 
035     float(FLOAT) 
036     true 
037     false 
038     desig(DESIG) 
  
039  'type' EXPRLIST 
040     exprlist(EXPR, EXPRLIST, POS) 
041     nil(POS) 
  
042  'type' OP 
043     less 
044     plus 
045     mult