Pascal Report  151  distinct characters occurring as string elements must denote different  values of type Char. The string element consisting of two apostrophes  denotes the apostrophe character.  CharacterString  = .. , ..  StringElement  !  StringElement  I  .. , ...  StringElement  =  .. , ,  ..  I  AnyCharacterExceptApostrophe .  A character string is a constant of type Char if it has one string element;  otherwise it is a constant of a string type (see Section 6.2.1) that has as  many components as there are string elements.  Note:  A character string must be written on just one line of program  text.  Examples of character strin/?s:  Symbol separators may be placed between any two adjacent symbols or  before the first symbol of a program. At least one symbol  separator  must occur between two adjacent identifiers, directives, word symbols,  labels, or numbers. A separator is a space, the end of a line of program  text, or a comment. The meaning of a program is unaltered if a comment  is replaced with a space.  Comment  =  ("{" I  "(*")  [CommentElement  J  ("j" I  "*)").  A  CommentElement  is  either an end of line or any  sequence of  characters not containing "]" or "*)".  Notes:  { ... *) and (* ... ) are valid comments. The comment {(*) is  equivalent to the comment {().  A constant definition introduces a constant identifier to denote the  value that is specified by the constant in the definition; the constant  identifier being defined must not occur in  the constant part of the  definition. Constant definitions are collected into constant definition  parts.  5.  Constants  'A'  'Pascal'  , .'  ,  '"  ,  'This  is a  character string' 