178  Pascal Report  10.2.  Scope  The label declaration part intr, )duces zero or more labels, each of  which must prefix one statement i  I  the statement part.  Block  =  LabelDeclarationPart Com 1I11fDejinitionPart TypeDefinitionPart  VariableDeclarationP art P  ,If  'edureAndFunctionDeclarationP art  StatementPart ,  LabelDeclarationPart  = [  "label'  f)igitSequence  [","  DigitSequence]  ";"] .  Label  =  DigitSequence .  The  spelling  of a label is the, pparent integral value that its digit  sequence describes in the usual d, 'cimal notation; the value must not  exceed 9999.  A definition or declaration introd Ices a spelling of an identifier or a  label and associates the  spellin~  with  a  specific meaning (e.g., a  variable identifier). The parts of a program in which every occurrence  of that spelling must take on that meaning are collectively called the  scope  of the introduction (definitit n or declaration). The occurrence of  a spelling in its introduction must precede every other occurrence of  that spelling within the scope of the introduction, with one exception.  The exception is that a type-identi fier spelling may occur as the domain  type of a pointer type (see Section 6.3) anywhere in the type definition  part that contains the spelling's introduction.  Each introduction is effective for some region of the program, as  described below. The scope of thl  introduction is that region less any  enclosed region for which anothe  introduction of the same spelling is  effective.  The following introductions ar  '.~  effective for the block in which the  introduction occurs:  a label in.  lahel declaration part; a constant  identifier in a constant definition  'art or in an enumerated type; a type  identifier in a type definition pal ;; a variable identifier in a variable  declaration part; a procedure iden ificr in a procedure declaration (see  Section 11.1); and a function ide!ltifier in a function declaration (see  Section 11.2). These labels and identifiers are said to be  local  to the  block.  The implicit introduction of  ~  andard predefined and predeclared 