Index  257  Difference,  see  Set difference  Digit  EBNF for, 149,220,226  ordering in type char, 18, 153  Sequence  EBNF for, 150,220,226  syntax diagram for, 11, 230  Directives, 13,149, 181, 183,212  EBNF for, 148  syntax diagram for, 13,230  (see also  Forward declaration)  Disjunction, 208  Dispose, 94, 101, 160,  191-192,  204,211  Div, 17,31,32,165-167,208  definition of, 167  precedence of, 32, 167  (see also  Arithmetic operators)  Division by zero, 168  Do,  see  Repetitive statements, With  statement  Domain type, of pointer, 145, 159  EBNFfor, 159,217,226  Downto,  see  For statement  Dynamic  allocation procedures, predeclared,  191  arrays, 7, 8  set of values of pointer type, 15  variables, 94, 145  EBNF  alphabetical, for Pascal, 225-229  cross reference of, 221-224  hierarchical, for Pascal, 215-220  of Polish notation, 113  (see also  Extended Backus-Naur  Form; also particular language  construct, EBNF for, e.g.  Array type, EBNF for)  ElementDescription, EBNF for,  165,219,226  Else,  see  If statement  Empty  parts of block, 1  file, 86, 158  set, 76-77,166  statement, 34, 44, 169  EBNF for, 169,218,226  End, and compound statements,  34, 172  End--{)f-file, 87, 159  (see also  Eof)  End--{)f-line, 9, 92, 93,134,150,  159, (see also  Eoln)  Entire Variable, 28  EBNF for, 162, 219, 226  Enumerated types, 15,50--53,143,  144,154, 153,210  EBNF for, 154, 217, 226  syntax diagram for, 50  Eof  and buffer variable, 87, 88,  132,  190  and file handling, 190  as predefined Boolean function,  17, 193,204,211  and write, 135  Eoln  and buffer variable, 92, 132, 164  and file handling, 92-93  as predefined Boolean function,  17,193,204,211  Equality,  see  Set equality,  Relational operators  Equivalence  17  (see also  Set operations)  Eratosthenes' sieve, 81  Error, and standards, 148,201  Evaluation  of buffer variables, 132, 133  order of, 30--32, 166  Exclusive or, 17  (see also  Boolean operators)  Exp,20,193,205,211  Exponential function,  see  Exp  Exponentiation  operator, 8  program for, 36, 123  Expressions, 28-32, 165-169  EBNF for, 165, 218, 226  evaluation of, 30--32  in assignment statement, 145  syntax diagram for, 32, 234 