Просмотр исходного текста страницы Синтаксис языка VHDL-2008

__NOTOC__
<center>'''Annex C'''
(informative)
</center>

'''Syntax summary'''

This annex provides a summary of the syntax for VHDL. Productions are ordered alphabetically by lefthand nonterminal name. The number listed to the right indicates the clause or subclause where the production is given.

{| class=standard align=center width=80%
! [[#A|A]]
! [[#B|B]]
! [[#C|C]]
! [[#D|D]]
! [[#E|E]]
! [[#F|F]]
! [[#G|G]]
! [[#I|I]]
! [[#L|L]]
! [[#M|M]]
! [[#N|N]]
! [[#O|O]]
! [[#P|P]]
! [[#Q|Q]]
! [[#R|R]]
! [[#S|S]]
! [[#T|T]]
! [[#U|U]]
! [[#V|V]]
! [[#W|W]]
|}


== A ==

 {{link|absolute_pathname}} ::= . {{ref|partial_pathname}}      [§ '''8.7''']


 {{link|abstract_literal}} ::= {{ref|decimal_literal}} | {{ref|based_literal}}      [§ '''15.5.1''']


 {{link|access_type_definition}} ::= '''access''' {{ref|subtype_indication}}      [§ '''5.4.1''']


 {{link|actual_designator}} ::=      [§ '''6.5.7.1''']
   [ '''inertial''' ] {{ref|expression}}
   | ''signal''_name
   | ''variable''_name
   | ''file''_name
   | {{ref|subtype_indication}}
   | ''subprogram_''name
   | ''instantiated_package_''name
   | '''open'''


 {{link|actual_parameter_part}} ::= ''parameter''_association_list      [§ '''9.3.4''']


 {{link|actual_part}} ::=      [§ '''6.5.7.1''']
   {{ref|actual_designator}}
   | ''function''_name ( {{ref|actual_designator}} )
   | {{ref|type_mark}} ( {{ref|actual_designator}} )


 {{link|adding_operator}} ::= + | – | &      [§ '''9.2''']


 {{link|aggregate}} ::=      [§ '''9.3.3.1''']
   ( {{ref|element_association}} { , {{ref|element_association}} } )


 {{link|alias_declaration}} ::=      [§ '''6.6.1''']
   '''alias''' {{ref|alias_designator}} [ : {{ref|subtype_indication}} ] '''is''' {{ref|name}} [ {{ref|signature}} ] ;


 {{link|alias_designator}} ::= {{ref|identifier}} | {{ref|character_literal}} | {{ref|operator_symbol}}      [§ '''6.6.1''']


 {{link|allocator}} ::=      [§ '''9.3.7''']
   '''new''' {{ref|subtype_indication}}
   | '''new''' {{ref|qualified_expression}}


 {{link|architecture_body}} ::=      [§ '''3.3.1''']
   '''architecture''' {{ref|identifier}}''' of''' ''entity''_name''' is'''
   {{ref|architecture_declarative_part}}
   '''begin'''
   {{ref|architecture_statement_part}}
   '''end''' [ '''architecture''' ] [ ''architecture''_simple_name ] ;


 {{link|architecture_declarative_part}} ::=      [§ '''3.3.2''']
   { {{ref|block_declarative_item}} }


 {{link|architecture_statement_part}} ::=      [§ '''3.3.3''']
   { {{ref|concurrent_statement}} }


 {{link|array_constraint}} ::=      [§ '''5.3.2.1''']
   {{ref|index_constraint}} [ {{ref|array_element_constraint}} ]
   | ( '''open''' ) [ {{ref|array_element_constraint}} ]


 {{link|array_element_constraint}} ::= {{ref|element_constraint}}      [§ '''5.3.2.1''']


 {{link|array_element_resolution}} ::= {{ref|resolution_indication}}      [§ '''6.3''']


 {{link|array_type_definition}} ::=      [§ '''5.3.2.1''']
   {{ref|unbounded_array_definition}} | {{ref|constrained_array_definition}}


 {{link|assertion}} ::=      [§ '''10.3''']
   '''assert''' {{ref|condition}}
   [ '''report''' {{ref|expression}} ]
   [ '''severity''' {{ref|expression}} ]


 {{link|assertion_statement}} ::= [ {{ref|label}} : ] {{ref|assertion}} ;      [§ '''10.3''']


 {{link|association_element}} ::=      [§ '''6.5.7.1''']
   [ {{ref|formal_part}} => ] {{ref|actual_part}}


 {{link|association_list}} ::=      [§ '''6.5.7.1''']
   {{ref|association_element}} { , {{ref|association_element}} }


 {{link|attribute_declaration}} ::=      [§ '''6.7''']
   '''attribute''' {{ref|identifier}} : {{ref|type_mark}} ;


 {{link|attribute_designator}} ::= ''attribute''_simple_name      [§ '''8.6''']


 {{link|attribute_name}} ::=      [§ '''8.6''']
   {{ref|prefix}} [ {{ref|signature}} ] ' {{ref|attribute_designator}} [ ( {{ref|expression}} ) ]


 {{link|attribute_specification}} ::=      [§ '''7.2''']
   '''attribute''' {{ref|attribute_designator}}''' of''' {{ref|entity_specification}}''' is''' {{ref|expression}} ;


== B ==

 {{link|base}} ::= {{ref|integer}}      [§ '''15.5.3''']


 {{link|base_specifier}} ::= B | O | X | UB | UO | UX | SB | SO | SX | D      [§ '''15.8''']


 {{link|based_integer}} ::=      [§ '''15.5.3''']
   {{ref|extended_digit}} { [ underline ] {{ref|extended_digit}} }


 {{link|based_literal}} ::=      [§ '''15.5.3''']
   {{ref|base}} # {{ref|based_integer}} [ . {{ref|based_integer}} ] # [ {{ref|exponent}} ]


 {{link|basic_character}} ::=      [§ '''15.2''']
   {{ref|basic_graphic_character}} | format_effector


 {{link|basic_graphic_character}} ::=      [§ '''15.2''']
   upper_case_letter | digit | special_character| space_character


 {{link|basic_identifier}} ::= {{ref|letter}} { [ underline ] {{ref|letter_or_digit}} }      [§ '''15.4.2''']


 {{link|binding_indication}} ::=      [§ '''7.3.2.1''']
   [ '''use''' {{ref|entity_aspect}} ]
   [ {{ref|generic_map_aspect}} ]
   [ {{ref|port_map_aspect}} ]


 {{link|bit_string_literal}} ::= [ {{ref|integer}} ] {{ref|base_specifier}} " [ {{ref|bit_value}} ] "      [§ '''15.8''']


 {{link|bit_value}} ::= {{ref|graphic_character}} { [ underline ] {{ref|graphic_character}} }      [§ '''15.8''']


 {{link|block_configuration}} ::=      [§ '''3.4.2''']
   '''for''' {{ref|block_specification}}
   { {{ref|use_clause}} }
   { {{ref|configuration_item}} }
   '''end for''' ;


 {{link|block_declarative_item}} ::=      [§ '''3.3.2''']
   {{ref|subprogram_declaration}}
   | {{ref|subprogram_body}}
   | {{ref|subprogram_instantiation_declaration}}
   | {{ref|package_declaration}}
   | {{ref|package_body}}
   | {{ref|package_instantiation_declaration}}
   | {{ref|type_declaration}}
   | {{ref|subtype_declaration}}
   | {{ref|constant_declaration}}
   | {{ref|signal_declaration}}
   | ''shared''_variable_declaration
   | {{ref|file_declaration}}
   | {{ref|alias_declaration}}
   | {{ref|component_declaration}}
   | {{ref|attribute_declaration}}
   | {{ref|attribute_specification}}
   | {{ref|configuration_specification}}
   | {{ref|disconnection_specification}}
   | {{ref|use_clause}}
   | {{ref|group_template_declaration}}
   | {{ref|group_declaration}}
   | ''PSL_''Property_Declaration
   | ''PSL_''Sequence_Declaration
   | ''PSL_''Clock_Declaration


 {{link|block_declarative_part}} ::=      [§ '''11.2''']
   { {{ref|block_declarative_item}} }


 {{link|block_header}} ::=      [§ '''11.2''']
   [ {{ref|generic_clause}}
   [ {{ref|generic_map_aspect}} ; ] ]
   [ {{ref|port_clause}}
   [ {{ref|port_map_aspect}} ; ] ]


 {{link|block_specification}} ::=      [§ '''3.4.2''']
   ''architecture''_name
   | ''block_statement''_label
   | ''generate_statement''_label [ ( {{ref|generate_specification}} ) ]


 {{link|block_statement}} ::=      [§ '''11.2''']
   ''block''_label :
   '''block''' [ ( ''guard''_condition ) ] [ '''is''' ]
   {{ref|block_header}}
   {{ref|block_declarative_part}}
   '''begin'''
   {{ref|block_statement_part}}
   '''end block''' [ ''block''_label ] ;


 {{link|block_statement_part}} ::=      [§ '''11.2''']
   { {{ref|concurrent_statement}} }


== C ==

 {{link|case_generate_alternative}} ::=      [§ '''11.8''']
   '''when''' [ ''alternative_''label : ] {{ref|choices}} =>
   {{ref|generate_statement_body}}


 {{link|case_generate_statement}} ::=      [§ '''11.8''']
   ''generate_''label :
   '''case''' {{ref|expression}}''' generate'''
   {{ref|case_generate_alternative}}
   { {{ref|case_generate_alternative}} }
   '''end generate''' [ ''generate_''label ] ;


 {{link|case_statement}} ::=      [§ '''10.9''']
   [ ''case''_label : ]
   '''case''' [ ? ] {{ref|expression}}''' is'''
   {{ref|case_statement_alternative}}
   { {{ref|case_statement_alternative}} }
   '''end case''' [ ? ] [ ''case''_label ] ;


 {{link|case_statement_alternative}} ::=      [§ '''10.9''']
   '''when''' {{ref|choices}} =>
   {{ref|sequence_of_statements}}


 {{link|character_literal}} ::= ' {{ref|graphic_character}} '      [§ '''15.6''']


 {{link|choice}} ::=      [§ '''9.3.3.1''']
   {{ref|simple_expression}}
   | {{ref|discrete_range}}
   | ''element''_simple_name
   | '''others'''


 {{link|choices}} ::= {{ref|choice}} { | {{ref|choice}} }      [§ '''9.3.3.1''']


 {{link|component_configuration}} ::=      [§ '''3.4.3''']
   '''for''' {{ref|component_specification}}
   [ {{ref|binding_indication}} ; ]
   { {{ref|verification_unit_binding_indication}} ; }
   [ {{ref|block_configuration}} ]
   '''end for''' ;


 {{link|component_declaration}} ::=      [§ '''6.8''']
   '''component''' {{ref|identifier}} [ '''is''' ]
   [ ''local''_generic_clause ]
   [ ''local''_port_clause ]
   '''end component''' [ ''component''_simple_name ] ;


 {{link|component_instantiation_statement}} ::=      [§ '''11.7.1''']
   ''instantiation''_label :
   {{ref|instantiated_unit}}
   [ {{ref|generic_map_aspect}} ]
   [ {{ref|port_map_aspect}} ] ;


 {{link|component_specification}} ::=      [§ '''7.3.1''']
   {{ref|instantiation_list}} : ''component''_name


 {{link|composite_type_definition}} ::=      [§ '''5.3.1''']
   {{ref|array_type_definition}}
   | {{ref|record_type_definition}}


 {{link|compound_configuration_specification}} ::=      [§ '''7.3.1''']
   '''for''' {{ref|component_specification}} {{ref|binding_indication}} ;
   {{ref|verification_unit_binding_indication}} ;
   { {{ref|verification_unit_binding_indication}} ; }
   '''end for''' ;


 {{link|concurrent_assertion_statement}} ::=      [§ '''11.5''']
   [ {{ref|label}} : ] [ '''postponed''' ] {{ref|assertion}} ;


 {{link|concurrent_conditional_signal_assignment}} ::=      [§ '''11.6''']
   {{ref|target}} <= [ '''guarded''' ] [ {{ref|delay_mechanism}} ] {{ref|conditional_waveforms}} ;


 {{link|concurrent_procedure_call_statement}} ::=      [§ '''11.4''']
   [ {{ref|label}} : ] [ '''postponed''' ] {{ref|procedure_call}} ;


 {{link|concurrent_selected_signal_assignment}} ::=      [§ '''11.6''']
   '''with''' {{ref|expression}}''' select''' [ ? ]
   {{ref|target}} <= [ '''guarded''' ] [ {{ref|delay_mechanism}} ] {{ref|selected_waveforms}} ;


 {{link|concurrent_signal_assignment_statement}} ::=      [§ '''11.6''']
   [ {{ref|label}} : ] [ '''postponed''' ] {{ref|concurrent_simple_signal_assignment}}
   | [ {{ref|label}} : ] [ '''postponed''' ] {{ref|concurrent_conditional_signal_assignment}}
   | [ {{ref|label}} : ] [ '''postponed''' ] {{ref|concurrent_selected_signal_assignment}}


 {{link|concurrent_simple_signal_assignment}} ::=      [§ '''11.6''']
   {{ref|target}} <= [ '''guarded''' ] [ {{ref|delay_mechanism}} ] {{ref|waveform}} ;


 {{link|concurrent_statement}} ::=      [§ '''11.1''']
   {{ref|block_statement}}
   | {{ref|process_statement}}
   | {{ref|concurrent_procedure_call_statement}}
   | {{ref|concurrent_assertion_statement}}
   | {{ref|concurrent_signal_assignment_statement}}
   | {{ref|component_instantiation_statement}}
   | {{ref|generate_statement}}
   | ''PSL_''PSL_Directive


 {{link|condition}} ::= {{ref|expression}}      [§ '''10.2''']


 {{link|condition_clause}} ::= '''until''' {{ref|condition}}      [§ '''10.2''']


 {{link|condition_operator}} ::= ??      [§ '''9.2.1''']


 {{link|conditional_expressions}} ::=      [§ '''10.5.3''']
   {{ref|expression}}''' when''' {{ref|condition}}
   { '''else''' {{ref|expression}}''' when''' {{ref|condition}} }
   [ '''else''' {{ref|expression}} ]


 {{link|conditional_force_assignment}} ::=      [§ '''10.5.3''']
   {{ref|target}} <= '''force''' [ {{ref|force_mode}} ] {{ref|conditional_expressions}} ;


 {{link|conditional_signal_assignment}} ::=      [§ '''10.5.3''']
   {{ref|conditional_waveform_assignment}}
   | {{ref|conditional_force_assignment}}


 {{link|conditional_variable_assignment}} ::=      [§ '''10.6.3''']
   {{ref|target}} := {{ref|conditional_expressions}} ;


 {{link|conditional_waveform_assignment}} ::=      [§ '''10.5.3''']
   {{ref|target}} <= [ {{ref|delay_mechanism}} ] {{ref|conditional_waveforms}} ;


 {{link|conditional_waveforms}} ::=      [§ '''10.5.3''']
   {{ref|waveform}}''' when''' {{ref|condition}}
   { '''else''' {{ref|waveform}}''' when''' {{ref|condition}} }
   [ '''else''' {{ref|waveform}} ]


 {{link|configuration_declaration}} ::=      [§ '''3.4.1''']
   '''configuration''' {{ref|identifier}}''' of''' ''entity''_name''' is'''
   {{ref|configuration_declarative_part}}
   { {{ref|verification_unit_binding_indication}} ; }
   {{ref|block_configuration}}
   '''end''' [ '''configuration''' ] [ ''configuration''_simple_name ] ;


 {{link|configuration_declarative_item}} ::=      [§ '''3.4.1''']
   {{ref|use_clause}}
   | {{ref|attribute_specification}}
   | {{ref|group_declaration}}


 {{link|configuration_declarative_part}} ::=      [§ '''3.4.1''']
   { {{ref|configuration_declarative_item}} }


 {{link|configuration_item}} ::=      [§ '''3.4.2''']
   {{ref|block_configuration}}
   | {{ref|component_configuration}}


 {{link|configuration_specification}} ::=      [§ '''7.3.1''']
   {{ref|simple_configuration_specification}}
   | {{ref|compound_configuration_specification}}


 {{link|constant_declaration}} ::=      [§ '''6.4.2.2''']
   '''constant''' {{ref|identifier_list}} : {{ref|subtype_indication}} [ := {{ref|expression}} ] ;


 {{link|constrained_array_definition}} ::=      [§ '''5.3.2.1''']
   '''array''' {{ref|index_constraint}}''' of''' ''element''_subtype_indication


 {{link|constraint}} ::=      [§ '''6.3''']
   {{ref|range_constraint}}
   | {{ref|array_constraint}}
   | {{ref|record_constraint}}


 {{link|context_clause}} ::= { {{ref|context_item}} }      [§ '''13.4''']


 {{link|context_declaration}} ::=      [§ '''13.3''']
   '''context''' {{ref|identifier}}''' is'''
   {{ref|context_clause}}
   '''end''' [ '''context''' ] [ ''context''_simple_name ] ;


 {{link|context_item}} ::=      [§ '''13.4''']
   {{ref|library_clause}}
   | {{ref|use_clause}}
   | {{ref|context_reference}}


 {{link|context_reference}} ::=      [§ '''13.4''']
   '''context''' {{ref|selected_name}} { , {{ref|selected_name}} } ;


== D ==

 {{link|decimal_literal}} ::= {{ref|integer}} [ . {{ref|integer}} ] [ {{ref|exponent}} ]      [§ '''15.5.2''']


 {{link|delay_mechanism}} ::=      [§ '''10.5.2.1''']
   '''transport'''
   | [ '''reject''' ''time''_expression ] '''inertial'''


 {{link|design_file}} ::= {{ref|design_unit}} { {{ref|design_unit}} }      [§ '''13.1''']


 {{link|design_unit}} ::= {{ref|context_clause}} {{ref|library_unit}}      [§ '''13.1''']


 {{link|designator}} ::= {{ref|identifier}} | {{ref|operator_symbol}}      [§ '''4.2.1''']


 {{link|direction}} ::= '''to''' | '''downto'''      [§ '''5.2.1''']


 {{link|disconnection_specification}} ::=      [§ '''7.4''']
   '''disconnect''' {{ref|guarded_signal_specification}}''' after''' ''time''_expression ;


 {{link|discrete_range}} ::= ''discrete''_subtype_indication | {{ref|range}}      [§ '''5.3.2.1''']


== E ==

 {{link|element_association}} ::=      [§ '''9.3.3.1''']
   [ {{ref|choices}} => ] {{ref|expression}}


 {{link|element_constraint}} ::=      [§ '''6.3''']
   {{ref|array_constraint}}
   | {{ref|record_constraint}}


 {{link|element_declaration}} ::=      [§ '''5.3.3''']
   {{ref|identifier_list}} : {{ref|element_subtype_definition}} ;


 {{link|element_resolution}} ::= {{ref|array_element_resolution}} | {{ref|record_resolution}}      [§ '''6.3''']


 {{link|element_subtype_definition}} ::= {{ref|subtype_indication}}      [§ '''5.3.3''']


 {{link|entity_aspect}} ::=      [§ '''7.3.2.2''']
   '''entity''' ''entity''_name [ ( ''architecture''_identifier ) ]
   | '''configuration''' ''configuration''_name
   | '''open'''


 {{link|entity_class}} ::=      [§ '''7.2''']
   '''entity'''
   | '''architecture'''
   | '''configuration'''
   | '''procedure'''
   | '''function'''
   | '''package'''
   | '''type'''
   | '''subtype'''
   | '''constant'''
   | '''signal'''
   | '''variable'''
   | '''component'''
   | '''label'''
   | '''literal'''
   | '''units'''
   | '''group'''
   | '''file'''
   | '''property'''
   | '''sequence'''


 {{link|entity_class_entry}} ::= {{ref|entity_class}} [ <> ]      [§ '''6.9''']


 {{link|entity_class_entry_list}} ::=      [§ '''6.9''']
   {{ref|entity_class_entry}} { , {{ref|entity_class_entry}} }


 {{link|entity_declaration}} ::=      [§ '''3.2.1''']
   '''entity''' {{ref|identifier}}''' is'''
   {{ref|entity_header}}
   {{ref|entity_declarative_part}}
   [ '''begin'''
   {{ref|entity_statement_part}} ]
   '''end''' [ '''entity''' ] [ ''entity''_simple_name ] ;


 {{link|entity_declarative_item}} ::=      [§ '''3.2.3''']
   {{ref|subprogram_declaration}}
   | {{ref|subprogram_body}}
   | {{ref|subprogram_instantiation_declaration}}
   | {{ref|package_declaration}}
   | {{ref|package_body}}
   | {{ref|package_instantiation_declaration}}
   | {{ref|type_declaration}}
   | {{ref|subtype_declaration}}
   | {{ref|constant_declaration}}
   | {{ref|signal_declaration}}
   | ''shared''_variable_declaration
   | {{ref|file_declaration}}
   | {{ref|alias_declaration}}
   | {{ref|attribute_declaration}}
   | {{ref|attribute_specification}}
   | {{ref|disconnection_specification}}
   | {{ref|use_clause}}
   | {{ref|group_template_declaration}}
   | {{ref|group_declaration}}
   | ''PSL_''Property_Declaration
   | ''PSL_''Sequence_Declaration
   | ''PSL_''Clock_Declaration


 {{link|entity_declarative_part}} ::=      [§ '''3.2.3''']
   { {{ref|entity_declarative_item}} }


 {{link|entity_designator}} ::= {{ref|entity_tag}} [ {{ref|signature}} ]      [§ '''7.2''']


 {{link|entity_header}} ::=      [§ '''3.2.3''']
   [ ''formal''_generic_clause ]
   [ ''formal''_port_clause ]


 {{link|entity_name_list}} ::=      [§ '''7.2''']
   {{ref|entity_designator}} { , {{ref|entity_designator}} }
   | '''others'''
   | '''all'''


 {{link|entity_specification}} ::=      [§ '''7.2''']
   {{ref|entity_name_list}} : {{ref|entity_class}}


 {{link|entity_statement}} ::=      [§ '''3.2.4''']
   {{ref|concurrent_assertion_statement}}
   | ''passive''_concurrent_procedure_call_statement
   | ''passive''_process_statement
   | ''PSL_''PSL_Directive


 {{link|entity_statement_part}} ::=      [§ '''3.2.4''']
   { {{ref|entity_statement}} }


 {{link|entity_tag}} ::= {{ref|simple_name}} | {{ref|character_literal}} | {{ref|operator_symbol}}      [§ '''7.2''']


 {{link|enumeration_literal}} ::= {{ref|identifier}} | {{ref|character_literal}}      [§ '''5.2.2.1''']


 {{link|enumeration_type_definition}} ::=      [§ '''5.2.2.1''']
   ( {{ref|enumeration_literal}} { , {{ref|enumeration_literal}} } )


 {{link|exit_statement}} ::=      [§ '''10.2''']
   [ {{ref|label}} : ] '''exit''' [ ''loop''_label ] [ '''when''' {{ref|condition}} ] ;


 {{link|exponent}} ::= E [ + ] {{ref|integer}} | E – {{ref|integer}}      [§ '''15.5.2''']


 {{link|expression}} ::=      [§ '''9.1''']
   {{ref|condition_operator}} {{ref|primary}}
   | {{ref|logical_expression}}


 {{link|extended_digit}} ::= digit | {{ref|letter}}      [§ '''15.5.3''']


 {{link|extended_identifier}} ::= \ {{ref|graphic_character}} { {{ref|graphic_character}} } \      [§ '''15.4.3''']


 {{link|external_name}} ::=      [§ '''8.7''']
   {{ref|external_constant_name}}
   | {{ref|external_signal_name}}
   | {{ref|external_variable_name}}


 {{link|external_constant_name}} ::=      [§ '''8.7''']
   << '''constant''' {{ref|external_pathname}} : {{ref|subtype_indication}} >>


 {{link|external_signal_name}} ::=      [§ '''8.7''']
   << '''signal''' {{ref|external_pathname}} : {{ref|subtype_indication}} >>


 {{link|external_variable_name}} ::=      [§ '''8.7''']
   << '''variable''' {{ref|external_pathname}} : {{ref|subtype_indication}} >>


 {{link|external_pathname}} ::=      [§ '''8.7''']
   {{ref|package_pathname}}
   | {{ref|absolute_pathname}}
   | {{ref|relative_pathname}}


== F ==

 {{link|factor}} ::=      [§ '''9.1''']
   {{ref|primary}} [ ** {{ref|primary}} ]
   | '''abs''' {{ref|primary}}
   | '''not''' {{ref|primary}}
   | {{ref|logical_operator}} {{ref|primary}}


 {{link|file_declaration}} ::=      [§ '''6.4.2.5''']
   '''file''' {{ref|identifier_list}} : {{ref|subtype_indication}} [ {{ref|file_open_information}} ] ;


 {{link|file_logical_name}} ::= ''string''_expression      [§ '''6.4.2.5''']


 {{link|file_open_information}} ::=      [§ '''6.4.2.5''']
   [ '''open''' ''file_open_kind''_expression ] '''is''' {{ref|file_logical_name}}


 {{link|file_type_definition}} ::=      [§ '''5.5.1''']
   '''file of''' {{ref|type_mark}}


 {{link|floating_type_definition}} ::= {{ref|range_constraint}}      [§ '''5.2.5.1''']


 {{link|for_generate_statement}} ::=      [§ '''11.8''']
   ''generate_''label :
   '''for''' ''generate_''parameter_specification''' generate'''
   {{ref|generate_statement_body}}
   '''end generate''' [ ''generate_''label ] ;


 {{link|force_mode}} ::= '''in''' | '''out'''      [§ '''10.5.2.1''']


 {{link|formal_designator}} ::=      [§ '''6.5.7.1''']
   ''generic''_name
   | ''port''_name
   | ''parameter''_name


 {{link|formal_parameter_list}} ::= ''parameter''_interface_list      [§ '''4.2.2.1''']


 {{link|formal_part}} ::=      [§ '''6.5.7.1''']
   {{ref|formal_designator}}
   | ''function''_name ( {{ref|formal_designator}} )
   | {{ref|type_mark}} ( {{ref|formal_designator}} )


 {{link|full_type_declaration}} ::=      [§ '''6.2''']
   '''type''' {{ref|identifier}}''' is''' {{ref|type_definition}} ;


 {{link|function_call}} ::=      [§ '''9.3.4''']
   ''function''_name [ ( {{ref|actual_parameter_part}} ) ]


 {{link|function_specification}} ::=      [§ '''4.2.1''']
   [ '''pure''' | '''impure''' ] '''function''' {{ref|designator}}
   {{ref|subprogram_header}}
   [ [ '''parameter''' ] ( {{ref|formal_parameter_list}} ) ] '''return''' {{ref|type_mark}}


== G ==

 {{link|generate_specification}} ::=      [§ '''3.4.2''']
   ''static''_discrete_range
   | ''static''_expression
   | ''alternative_''label


 {{link|generate_statement}} ::=      [§ '''11.8''']
   {{ref|for_generate_statement}}
   | {{ref|if_generate_statement}}
   | {{ref|case_generate_statement}}


 {{link|generate_statement_body}} ::=      [§ '''11.8''']
   [ {{ref|block_declarative_part}}
   '''begin''' ]
   { {{ref|concurrent_statement}} }
   [ '''end''' [ ''alternative_''label ] ; ]


 {{link|generic_clause}} ::=      [§ '''6.5.6.2''']
   '''generic''' ( {{ref|generic_list}} ) ;


 {{link|generic_list}} ::= ''generic''_interface_list      [§ '''6.5.6.2''']


 {{link|generic_map_aspect}} ::=      [§ '''6.5.6.2''']
   '''generic map''' ( ''generic''_association_list )


 {{link|graphic_character}} ::=      [§ '''15.2''']
   {{ref|basic_graphic_character}} | lower_case_letter | other_special_character


 {{link|group_constituent}} ::= {{ref|name}} | {{ref|character_literal}}      [§ '''6.10''']


 {{link|group_constituent_list}} ::= {{ref|group_constituent}} { , {{ref|group_constituent}} }      [§ '''6.10''']


 {{link|group_declaration}} ::=      [§ '''6.10''']
   '''group''' {{ref|identifier}} : ''group_template''_name ( {{ref|group_constituent_list}} ) ;


 {{link|group_template_declaration}} ::=      [§ '''6.9''']
   '''group''' {{ref|identifier}}''' is''' ( {{ref|entity_class_entry_list}} ) ;


 {{link|guarded_signal_specification}} ::=      [§ '''7.4''']
   ''guarded''_signal_list : {{ref|type_mark}}


== I ==

 {{link|identifier}} ::= {{ref|basic_identifier}} | {{ref|extended_identifier}}      [§ '''15.4.1''']


 {{link|identifier_list}} ::= {{ref|identifier}} { , {{ref|identifier}} }      [§ '''5.3.3''']


 {{link|if_generate_statement}} ::=      [§ '''11.8''']
   ''generate_''label :
   '''if''' [ ''alternative_''label : ] {{ref|condition}}''' generate'''
   {{ref|generate_statement_body}}
   { '''elsif''' [ ''alternative_''label : ] {{ref|condition}}''' generate'''
   {{ref|generate_statement_body}} }
   [ '''else''' [ ''alternative_''label : ] '''generate'''
   {{ref|generate_statement_body}} ]
   '''end generate''' [ ''generate_''label ] ;


 {{link|if_statement}} ::=      [§ '''10.8''']
   [ ''if_''label : ]
   '''if''' {{ref|condition}}''' then'''
   {{ref|sequence_of_statements}}
   { '''elsif''' {{ref|condition}} t'''hen'''
   {{ref|sequence_of_statements}} }
   [ '''else'''
   {{ref|sequence_of_statements}} ]
   '''end if''' [ ''if''_label ] ;


 {{link|incomplete_type_declaration}} ::= '''type''' {{ref|identifier}} ;      [§ '''5.4.2''']


 {{link|index_constraint}} ::= ( {{ref|discrete_range}} { , {{ref|discrete_range}} } )      [§ '''5.3.2.1''']


 {{link|index_subtype_definition}} ::= {{ref|type_mark}}''' {{ref|range}}''' <>      [§ '''5.3.2.1''']


 {{link|indexed_name}} ::= {{ref|prefix}} ( {{ref|expression}} { , {{ref|expression}} } )      [§ '''8.4''']


 {{link|instantiated_unit}} ::=      [§ '''11.7.1''']
   [ '''component''' ] ''component''_name
   | '''entity''' ''entity''_name [ ( ''architecture''_identifier ) ]
   | '''configuration''' ''configuration''_name


 {{link|instantiation_list}} ::=      [§ '''7.3.1''']
   ''instantiation''_label { , ''instantiation''_label }
   | '''others'''
   | '''all'''


 {{link|integer}} ::= digit { [ underline ] digit }      [§ '''15.5.2''']


 {{link|integer_type_definition}} ::= {{ref|range_constraint}}      [§ '''5.2.3.1''']


 {{link|interface_constant_declaration}} ::=      [§ '''6.5.2''']
   [ '''constant''' ] {{ref|identifier_list}} : [ '''in''' ] {{ref|subtype_indication}} [ := ''static''_expression ]


 {{link|interface_declaration}} ::=      [§ '''6.5.1''']
   {{ref|interface_object_declaration}}
   | {{ref|interface_type_declaration}}
   | {{ref|interface_subprogram_declaration}}
   | {{ref|interface_package_declaration}}


 {{link|interface_element}} ::= {{ref|interface_declaration}}      [§ '''6.5.6.1''']


 {{link|interface_file_declaration}} ::=      [§ '''6.5.2''']
   '''file''' {{ref|identifier_list}} : {{ref|subtype_indication}}


 {{link|interface_function_specification}} ::=      [§ '''6.5.4''']
   [ '''pure''' | '''impure''' ] '''function''' {{ref|designator}}
   [ [ '''parameter''' ] ( {{ref|formal_parameter_list}} ) ] '''return''' {{ref|type_mark}}


 {{link|interface_incomplete_type_declaration}} ::= '''type''' {{ref|identifier}}      [§ '''6.5.3''']


 {{link|interface_list}} ::=      [§ '''6.5.6.1''']
   {{ref|interface_element}} { ; {{ref|interface_element}} }


 {{link|interface_object_declaration}} ::=      [§ '''6.5.2''']
   {{ref|interface_constant_declaration}}
   | {{ref|interface_signal_declaration}}
   | {{ref|interface_variable_declaration}}
   | {{ref|interface_file_declaration}}


 {{link|interface_package_declaration}} ::=      [§ '''6.5.5''']
   '''package''' {{ref|identifier}}''' is'''
   '''new''' ''uninstantiated_package_''name {{ref|interface_package_generic_map_aspect}}


 {{link|interface_package_generic_map_aspect}} ::=      [§ '''6.5.5''']
   {{ref|generic_map_aspect}}
   | '''generic map''' ( <> )
   | '''generic map''' ( '''default''' )


 {{link|interface_procedure_specification}} ::=      [§ '''6.5.4''']
   '''procedure''' {{ref|designator}}
   [ [ '''parameter''' ] ( {{ref|formal_parameter_list}} ) ]


 {{link|interface_signal_declaration}} ::=      [§ '''6.5.2''']
   [ '''signal''' ] {{ref|identifier_list}} : [ {{ref|mode}} ] {{ref|subtype_indication}} [ '''bus''' ] [ := ''static''_expression ]


 {{link|interface_subprogram_declaration}} ::=      [§ '''6.5.4''']
   {{ref|interface_subprogram_specification}} [ '''is''' {{ref|interface_subprogram_default}} ]


 {{link|interface_subprogram_default}} ::= ''subprogram_''name | <>      [§ '''6.5.4''']


 {{link|interface_subprogram_specification}} ::=      [§ '''6.5.4''']
   {{ref|interface_procedure_specification}} | {{ref|interface_function_specification}}


 {{link|interface_type_declaration}} ::=      [§ '''6.5.3''']
   {{ref|interface_incomplete_type_declaration}}


 {{link|interface_variable_declaration}} ::=      [§ '''6.5.2''']
   [ '''variable''' ] {{ref|identifier_list}} : [ {{ref|mode}} ] {{ref|subtype_indication}} [ := ''static''_expression ]


 {{link|iteration_scheme}} ::=      [§ '''10.10''']
   '''while''' {{ref|condition}}
   | '''for''' ''loop''_parameter_specification


== L ==

 {{link|label}} ::= {{ref|identifier}}      [§ '''11.8''']


 {{link|letter}} ::= upper_case_letter | lower_case_letter      [§ '''15.4.2''']


 {{link|letter_or_digit}} ::= {{ref|letter}} | digit      [§ '''15.4.2''']


 {{link|library_clause}} ::= '''library''' {{ref|logical_name_list}} ;      [§ '''13.2''']


 {{link|library_unit}} ::=      [§ '''13.1''']
   {{ref|primary_unit}}
   | {{ref|secondary_unit}}


 {{link|literal}} ::=      [§ '''9.3.2''']
   {{ref|numeric_literal}}
   | {{ref|enumeration_literal}}
   | {{ref|string_literal}}
   | {{ref|bit_string_literal}}
   | '''null'''


 {{link|logical_expression}} ::=      [§ '''9.1''']
   {{ref|relation}} { '''and''' {{ref|relation}} }
   | {{ref|relation}} { '''or''' {{ref|relation}} }
   | {{ref|relation}} { '''xor''' {{ref|relation}} }
   | {{ref|relation}} [ '''nand''' {{ref|relation}} ]
   | {{ref|relation}} [ '''nor''' {{ref|relation}} ]
   | {{ref|relation}} { '''xnor''' {{ref|relation}} }


 {{link|logical_name}} ::= {{ref|identifier}}      [§ '''13.2''']


 {{link|logical_name_list}} ::= {{ref|logical_name}} { , {{ref|logical_name}} }      [§ '''13.2''']


 {{link|logical_operator}} ::= '''and''' | '''or''' | '''nand''' | '''nor''' | '''xor''' | '''xnor'''      [§ '''9.2.1''']


 {{link|loop_statement}} ::=      [§ '''10.10''']
   [ ''loop''_label : ]
   [ {{ref|iteration_scheme}} ] '''loop'''
   {{ref|sequence_of_statements}}
   '''end loop''' [ ''loop''_label ] ;


== M ==

 {{link|miscellaneous_operator}} ::= ** | '''abs''' | '''not'''      [§ '''9.2.1''']


 {{link|mode}} ::= '''in''' | '''out''' | '''inout''' | '''buffer''' | '''linkage'''      [§ '''6.5.2''']


 {{link|multiplying_operator}} ::= * | / | '''mod''' | '''rem'''      [§ '''9.2.1''']


== N ==

 {{link|name}} ::=      [§ '''8.1''']
   {{ref|simple_name}}
   | {{ref|operator_symbol}}
   | {{ref|character_literal}}
   | {{ref|selected_name}}
   | {{ref|indexed_name}}
   | {{ref|slice_name}}
   | {{ref|attribute_name}}
   | {{ref|external_name}}


 {{link|next_statement}} ::=      [§ '''10.11''']
   [ {{ref|label}} : ] '''next''' [ ''loop''_label ] [ '''when''' {{ref|condition}} ] ;


 {{link|null_statement}} ::= [ {{ref|label}} : ] '''null''' ;      [§ '''10.14''']


 {{link|numeric_literal}} ::=      [§ '''9.3.2''']
   {{ref|abstract_literal}}
   | {{ref|physical_literal}}


== O ==

 {{link|object_declaration}} ::=      [§ '''6.4.2.1''']
   {{ref|constant_declaration}}
   | {{ref|signal_declaration}}
   | {{ref|variable_declaration}}
   | {{ref|file_declaration}}


 {{link|operator_symbol}} ::= {{ref|string_literal}}      [§ '''4.2.1''']


== P ==

 {{link|package_body}} ::=      [§ '''4.8''']
   '''package body''' ''package''_simple_name''' is'''
   {{ref|package_body_declarative_part}}
   '''end''' [ '''package body''' ] [ ''package''_simple_name ] ;


 {{link|package_body_declarative_item}} ::=      [§ '''4.8''']
   {{ref|subprogram_declaration}}
   | {{ref|subprogram_body}}
   | {{ref|subprogram_instantiation_declaration}}
   | {{ref|package_declaration}}
   | {{ref|package_body}}
   | {{ref|package_instantiation_declaration}}
   | {{ref|type_declaration}}
   | {{ref|subtype_declaration}}
   | {{ref|constant_declaration}}
   | {{ref|variable_declaration}}
   | {{ref|file_declaration}}
   | {{ref|alias_declaration}}
   | {{ref|attribute_declaration}}
   | {{ref|attribute_specification}}
   | {{ref|use_clause}}
   | {{ref|group_template_declaration}}
   | {{ref|group_declaration}}


 {{link|package_body_declarative_part}} ::=      [§ '''4.8''']
   { {{ref|package_body_declarative_item}} }


 {{link|package_declaration}} ::=      [§ '''4.7''']
   '''package''' {{ref|identifier}}''' is'''
   {{ref|package_header}}
   {{ref|package_declarative_part}}
   '''end''' [ '''package''' ] [ ''package''_simple_name ] ;


 {{link|package_declarative_item}} ::=      [§ '''4.7''']
   {{ref|subprogram_declaration}}
   | {{ref|subprogram_instantiation_declaration}}
   | {{ref|package_declaration}}
   | {{ref|package_instantiation_declaration}}
   | {{ref|type_declaration}}
   | {{ref|subtype_declaration}}
   | {{ref|constant_declaration}}
   | {{ref|signal_declaration}}
   | {{ref|variable_declaration}}
   | {{ref|file_declaration}}
   | {{ref|alias_declaration}}
   | {{ref|component_declaration}}
   | {{ref|attribute_declaration}}
   | {{ref|attribute_specification}}
   | {{ref|disconnection_specification}}
   | {{ref|use_clause}}
   | {{ref|group_template_declaration}}
   | {{ref|group_declaration}}
   | ''PSL_''Property_Declaration
   | ''PSL_''Sequence_Declaration


 {{link|package_declarative_part}} ::=      [§ '''4.7''']
   { {{ref|package_declarative_item}} }


 {{link|package_header}} ::=      [§ '''4.7''']
   [ {{ref|generic_clause}}
   [ {{ref|generic_map_aspect}} ; ] ]


 {{link|package_instantiation_declaration}} ::=      [§ '''4.9''']
   '''package''' {{ref|identifier}}''' is new''' ''uninstantiated_package_''name
   [ {{ref|generic_map_aspect}} ] ;


 {{link|package_pathname}} ::=
   @ ''library_''logical_name . { ''package_''simple_name . } ''object_''simple_name [§ '''8.7''']


 {{link|parameter_specification}} ::=      [§ '''10.10''']
   {{ref|identifier}}''' in''' {{ref|discrete_range}}


 {{link|partial_pathname}} ::= { {{ref|pathname_element}} . } ''object_''simple_name      [§ '''8.7''']


 {{link|pathname_element}} ::=      [§ '''8.7''']
   ''entity_''simple_name
   | ''component_instantiation_''label
   | ''block_''label
   | ''generate_statement_''label [ ( ''static_''expression ) ]
   | ''package_''simple_name


 {{link|physical_literal}} ::= [ {{ref|abstract_literal}} ] ''unit''_name      [§ '''5.2.4.1''']


 {{link|physical_type_definition}} ::=      [§ '''5.2.4.1''']
   {{ref|range_constraint}}
   '''units'''
   {{ref|primary_unit_declaration}}
   { {{ref|secondary_unit_declaration}} }
   '''end units''' [ ''physical_type''_simple_name ]


 {{link|port_clause}} ::=      [§ '''6.5.6.3''']
   '''port''' ( {{ref|port_list}} ) ;


 {{link|port_list}} ::= ''port''_interface_list      [§ '''6.5.6.3''']


 {{link|port_map_aspect}} ::=      [§ '''6.5.7.3''']
   '''port map''' ( ''port''_association_list )


 {{link|prefix}} ::=      [§ '''8.1''']
   {{ref|name}}
   | {{ref|function_call}}


 {{link|primary}} ::=      [§ '''9.1''']
   {{ref|name}}
   | {{ref|literal}}
   | {{ref|aggregate}}
   | {{ref|function_call}}
   | {{ref|qualified_expression}}
   | {{ref|type_conversion}}
   | {{ref|allocator}}
   | ( {{ref|expression}} )


 {{link|primary_unit}} ::=      [§ '''13.1''']
   {{ref|entity_declaration}}
   | {{ref|configuration_declaration}}
   | {{ref|package_declaration}}
   | {{ref|package_instantiation_declaration}}
   | {{ref|context_declaration}}
   | ''PSL_''Verification_Unit


 {{link|primary_unit_declaration}} ::= {{ref|identifier}} ;      [§ '''5.2.4.1''']


 {{link|procedure_call}} ::= ''procedure''_name [ ( {{ref|actual_parameter_part}} ) ]      [§ '''10.7''']


 {{link|procedure_call_statement}} ::= [ {{ref|label}} : ] {{ref|procedure_call}} ;      [§ '''10.7''']


 {{link|procedure_specification}} ::=      [§ '''4.2.1''']
   '''procedure''' {{ref|designator}}
   {{ref|subprogram_header}}
   [ [ '''parameter''' ] ( {{ref|formal_parameter_list}} ) ]


 {{link|process_declarative_item}} ::=      [§ '''11.3''']
   {{ref|subprogram_declaration}}
   | {{ref|subprogram_body}}
   | {{ref|subprogram_instantiation_declaration}}
   | {{ref|package_declaration}}
   | {{ref|package_body}}
   | package instantiation_declaration
   | {{ref|type_declaration}}
   | {{ref|subtype_declaration}}
   | {{ref|constant_declaration}}
   | {{ref|variable_declaration}}
   | {{ref|file_declaration}}
   | {{ref|alias_declaration}}
   | {{ref|attribute_declaration}}
   | {{ref|attribute_specification}}
   | {{ref|use_clause}}
   | {{ref|group_template_declaration}}
   | {{ref|group_declaration}}


 {{link|process_declarative_part}} ::=      [§ '''11.3''']
   { {{ref|process_declarative_item}} }


 {{link|process_sensitivity_list}} ::= '''all''' | {{ref|sensitivity_list}}      [§ '''11.3''']


 {{link|process_statement}} ::=      [§ '''11.3''']
   [ ''process''_label : ]
   [ '''postponed''' ] '''process''' [ ( {{ref|process_sensitivity_list}} ) ] [ '''is''' ]
   {{ref|process_declarative_part}}
   '''begin'''
   {{ref|process_statement_part}}
   '''end''' [ '''postponed''' ] '''process''' [ ''process''_label ] ;


 {{link|process_statement_part}} ::=      [§ '''11.3''']
   { {{ref|sequential_statement}} }


 {{link|protected_type_body}} ::=      [§ '''5.6.3''']
   '''protected body'''
   {{ref|protected_type_body_declarative_part}}
   '''end protected body''' [ ''protected_type''_simple {{ref|name}} ]


 {{link|protected_type_body_declarative_item}} ::=      [§ '''5.6.3''']
   {{ref|subprogram_declaration}}
   | {{ref|subprogram_body}}
   | {{ref|subprogram_instantiation_declaration}}
   | {{ref|package_declaration}}
   | {{ref|package_body}}
   | {{ref|package_instantiation_declaration}}
   | {{ref|type_declaration}}
   | {{ref|subtype_declaration}}
   | {{ref|constant_declaration}}
   | {{ref|variable_declaration}}
   | {{ref|file_declaration}}
   | {{ref|alias_declaration}}
   | {{ref|attribute_declaration}}
   | {{ref|attribute_specification}}
   | {{ref|use_clause}}
   | {{ref|group_template_declaration}}
   | {{ref|group_declaration}}


 {{link|protected_type_body_declarative_part}} ::=      [§ '''5.6.3''']
   { {{ref|protected_type_body_declarative_item}} }


 {{link|protected_type_declaration}} ::=      [§ '''5.6.2''']
   '''protected'''
   {{ref|protected_type_declarative_part}}
   '''end protected''' [ ''protected_type''_simple_name ]


 {{link|protected_type_declarative_item}} ::=      [§ '''5.6.2''']
   {{ref|subprogram_declaration}}
   | {{ref|subprogram_instantiation_declaration}}
   | {{ref|attribute_specification}}
   | {{ref|use_clause}}


 {{link|protected_type_declarative_part}} ::=      [§ '''5.6.2''']
   { {{ref|protected_type_declarative_item}} }


 {{link|protected_type_definition}} ::=      [§ '''5.6.1''']
   {{ref|protected_type_declaration}}
   | {{ref|protected_type_body}}


== Q ==

 {{link|qualified_expression}} ::=      [§ '''9.3.5''']
   {{ref|type_mark}} ' ( {{ref|expression}} )
   | {{ref|type_mark}} ' {{ref|aggregate}}


== R ==

 {{link|range}} ::=      [§ '''5.2.1''']
   ''range''_attribute_name
   | {{ref|simple_expression}} {{ref|direction}} {{ref|simple_expression}}


 {{link|range_constraint}} ::= '''range''' {{ref|range}}      [§ '''5.2.1''']


 {{link|record_constraint}} ::=      [§ '''5.3.3''']
   ( {{ref|record_element_constraint}} { , {{ref|record_element_constraint}} } )


 {{link|record_element_constraint}} ::= ''record_element_''simple_name {{ref|element_constraint}}      [§ '''5.3.3''']


 {{link|record_element_resolution}} ::= ''record_element_''simple_name {{ref|resolution_indication}}      [§ '''6.3''']


 {{link|record_resolution}} ::= {{ref|record_element_resolution}} { , {{ref|record_element_resolution}} }      [§ '''6.3''']


 {{link|record_type_definition}} ::=      [§ '''5.3.3''']
   '''record'''
   {{ref|element_declaration}}
   { {{ref|element_declaration}} }
   '''end record''' [ ''record_type''_simple_name ]


 {{link|relation}} ::=      [§ '''9.1''']
   {{ref|shift_expression}} [ {{ref|relational_operator}} {{ref|shift_expression}} ]


 {{link|relational_operator}} ::= = | /= | < | <= | > | >= | ?= | ?/= | ?< | ?<= | ?> | ?>=      [§ '''9.2.1''']


 {{link|relative_pathname}} ::= { ^ . } {{ref|partial_pathname}}      [§ '''8.7''']


 {{link|report_statement}} ::=      [§ '''10.4''']
   [ {{ref|label}} : ]
   '''report''' {{ref|expression}}
   [ '''severity''' {{ref|expression}} ] ;


 {{link|resolution_indication}} ::=      [§ '''6.3''']
   ''resolution_function_''name | ( {{ref|element_resolution}} )


 {{link|return_statement}} ::=      [§ '''10.13''']
   [ {{ref|label}} : ] '''return''' [ {{ref|expression}} ] ;


== S ==

 {{link|scalar_type_definition}} ::=      [§ '''5.2.1''']
   {{ref|enumeration_type_definition}}
   | {{ref|integer_type_definition}}
   | {{ref|floating_type_definition}}
   | {{ref|physical_type_definition}}


 {{link|secondary_unit}} ::=      [§ '''13.1''']
   {{ref|architecture_body}}
   | {{ref|package_body}}


 {{link|secondary_unit_declaration}} ::= {{ref|identifier}} = {{ref|physical_literal}} ;      [§ '''5.2.4.1''']


 {{link|selected_expressions}} ::=      [§ '''10.5.4''']
   { {{ref|expression}}''' when''' {{ref|choices}} , }
   {{ref|expression}}''' when''' {{ref|choices}}


 {{link|selected_force_assignment}} ::=      [§ '''10.5.4''']
   '''with''' {{ref|expression}}''' select''' [ ? ]
   {{ref|target}} <= '''force''' [ {{ref|force_mode}} ] {{ref|selected_expressions}} ;


 {{link|selected_name}} ::= {{ref|prefix}} . {{ref|suffix}}      [§ '''8.3''']


 {{link|selected_signal_assignment}} ::=      [§ '''10.5.4''']
   {{ref|selected_waveform_assignment}}
   | {{ref|selected_force_assignment}}


 {{link|selected_variable_assignment}} ::=      [§ '''10.6.4''']
   '''with''' {{ref|expression}}''' select''' [ ? ]
   {{ref|target}} := {{ref|selected_expressions}} ;


 {{link|selected_waveform_assignment}} ::=      [§ '''10.5.4''']
   '''with''' {{ref|expression}}''' select''' [ ? ]
   {{ref|target}} <= [ {{ref|delay_mechanism}} ] {{ref|selected_waveforms}} ;


 {{link|selected_waveforms}} ::=      [§ '''10.5.4''']
   { {{ref|waveform}}''' when''' {{ref|choices}} , }
   {{ref|waveform}}''' when''' {{ref|choices}}


 {{link|sensitivity_clause}} ::= '''on''' {{ref|sensitivity_list}}      [§ '''10.2''']


 {{link|sensitivity_list}} ::= ''signal''_name { , ''signal''_name }      [§ '''10.2''']


 {{link|sequence_of_statements}} ::=      [§ '''10.1''']
   { {{ref|sequential_statement}} }


 {{link|sequential_statement}} ::=      [§ '''10.1''']
   {{ref|wait_statement}}
   | {{ref|assertion_statement}}
   | {{ref|report_statement}}
   | {{ref|signal_assignment_statement}}
   | {{ref|variable_assignment_statement}}
   | {{ref|procedure_call_statement}}
   | {{ref|if_statement}}
   | {{ref|case_statement}}
   | {{ref|loop_statement}}
   | {{ref|next_statement}}
   | {{ref|exit_statement}}
   | {{ref|return_statement}}
   | {{ref|null_statement}}


 {{link|shift_expression}} ::=      [§ '''9.1''']
   {{ref|simple_expression}} [ {{ref|shift_operator}} {{ref|simple_expression}} ]


 {{link|shift_operator}} ::= '''sll''' | '''srl''' | '''sla''' | '''sra''' | '''rol''' | '''ror'''      [§ '''9.2.1''']


 {{link|sign}} ::= + | –      [§ '''9.2.1''']


 {{link|signal_assignment_statement}} ::=      [§ '''10.5.1''']
   [ {{ref|label}} : ] {{ref|simple_signal_assignment}}
   | [ {{ref|label}} : ] {{ref|conditional_signal_assignment}}
   | [ {{ref|label}} : ] {{ref|selected_signal_assignment}}


 {{link|signal_declaration}} ::=      [§ '''6.4.2.3''']
   '''signal''' {{ref|identifier_list}} : {{ref|subtype_indication}} [ {{ref|signal_kind}} ] [ := {{ref|expression}} ] ;


 {{link|signal_kind}} ::= '''register''' | '''bus'''      [§ '''6.4.2.3''']


 {{link|signal_list}} ::=      [§ '''7.4''']
   ''signal''_name { , ''signal''_name }
   | '''others'''
   | '''all'''


 {{link|signature}} ::= [ [ {{ref|type_mark}} { , {{ref|type_mark}} } ] [ '''return''' {{ref|type_mark}} ] ]      [§ '''4.5.3''']


 {{link|simple_configuration_specification}} ::=      [§ '''7.3.1''']
   '''for''' {{ref|component_specification}} {{ref|binding_indication}} ;
   [ '''end for''' ; ]


 {{link|simple_expression}} ::=      [§ '''9.1''']
   [ {{ref|sign}} ] {{ref|term}} { {{ref|adding_operator}} {{ref|term}} }


 {{link|simple_force_assignment}} ::=      [§ '''10.5.2.1''']
   {{ref|target}} <= '''force''' [ {{ref|force_mode}} ] {{ref|expression}} ;


 {{link|simple_name}} ::= {{ref|identifier}}      [§ '''8.2''']


 {{link|simple_release_assignment}} ::=      [§ '''10.5.2.1''']
   {{ref|target}} <= '''release''' [ {{ref|force_mode}} ] ;


 {{link|simple_signal_assignment}} ::=      [§ '''10.5.2.1''']
   {{ref|simple_waveform_assignment}}
   | {{ref|simple_force_assignment}}
   | {{ref|simple_release_assignment}}


 {{link|simple_waveform_assignment}} ::=      [§ '''10.5.2.1''']
   {{ref|target}} <= [ {{ref|delay_mechanism}} ] {{ref|waveform}} ;


 {{link|simple_variable_assignment}} ::=      [§ '''10.6.2.1''']
   {{ref|target}} := {{ref|expression}} ;


 {{link|slice_name}} ::= {{ref|prefix}} ( {{ref|discrete_range}} )      [§ '''8.5''']


 {{link|string_literal}} ::= " { {{ref|graphic_character}} } "      [§ '''15.7''']


 {{link|subprogram_body}} ::=      [§ '''4.3''']
   {{ref|subprogram_specification}}''' is'''
   {{ref|subprogram_declarative_part}}
   '''begin'''
   {{ref|subprogram_statement_part}}
   '''end''' [ {{ref|subprogram_kind}} ] [ {{ref|designator}} ] ;


 {{link|subprogram_declaration}} ::=      [§ '''4.2.1''']
   {{ref|subprogram_specification}} ;


 {{link|subprogram_declarative_item}} ::=      [§ '''4.3''']
   {{ref|subprogram_declaration}}
   | {{ref|subprogram_body}}
   | {{ref|subprogram_instantiation_declaration}}
   | {{ref|package_declaration}}
   | {{ref|package_body}}
   | {{ref|package_instantiation_declaration}}
   | {{ref|type_declaration}}
   | {{ref|subtype_declaration}}
   | {{ref|constant_declaration}}
   | {{ref|variable_declaration}}
   | {{ref|file_declaration}}
   | {{ref|alias_declaration}}
   | {{ref|attribute_declaration}}
   | {{ref|attribute_specification}}
   | {{ref|use_clause}}
   | {{ref|group_template_declaration}}
   | {{ref|group_declaration}}


 {{link|subprogram_declarative_part}} ::=      [§ '''4.3''']
   { {{ref|subprogram_declarative_item}} }


 {{link|subprogram_header}} ::=      [§ '''4.2.1''']
   [ '''generic''' ( {{ref|generic_list}} )
   [ {{ref|generic_map_aspect}} ] ]


 {{link|subprogram_instantiation_declaration}} ::=      [§ '''4.4''']
   {{ref|subprogram_kind}} {{ref|identifier}}''' is new''' ''uninstantiated_subprogram_''name [ {{ref|signature}} ]
   [ {{ref|generic_map_aspect}} ] ;


 {{link|subprogram_kind}} ::= '''procedure''' | '''function'''      [§ '''4.3''']


 {{link|subprogram_specification}} ::=      [§ '''4.2.1''']
   {{ref|procedure_specification}} | {{ref|function_specification}}


 {{link|subprogram_statement_part}} ::=      [§ '''4.3''']
   { {{ref|sequential_statement}} }


 {{link|subtype_declaration}} ::=      [§ '''6.3''']
   '''subtype''' {{ref|identifier}} is {{ref|subtype_indication}} ;


 {{link|subtype_indication}} ::=      [§ '''6.3''']
   [ {{ref|resolution_indication}} ] {{ref|type_mark}} [ {{ref|constraint}} ]


 {{link|suffix}} ::=      [§ '''8.3''']
   {{ref|simple_name}}
   | {{ref|character_literal}}
   | {{ref|operator_symbol}}
   | '''all'''


== T ==

 {{link|target}} ::=      [§ '''10.5.2.1''']
   {{ref|name}}
   | {{ref|aggregate}}


 {{link|term}} ::=      [§ '''9.1''']
   {{ref|factor}} { {{ref|multiplying_operator}} {{ref|factor}} }


 {{link|timeout_clause}} ::= '''for''' ''time''_expression      [§ '''10.2''']


 {{link|tool_directive}} ::= ` {{ref|identifier}} { {{ref|graphic_character}} }      [§ '''15.11''']


 {{link|type_conversion}} ::= {{ref|type_mark}} ( {{ref|expression}} )      [§ '''9.3.6''']


 {{link|type_declaration}} ::=      [§ '''6.2''']
   {{ref|full_type_declaration}}
   | {{ref|incomplete_type_declaration}}


 {{link|type_definition}} ::=      [§ '''6.2''']
   {{ref|scalar_type_definition}}
   | {{ref|composite_type_definition}}
   | {{ref|access_type_definition}}
   | {{ref|file_type_definition}}
   | {{ref|protected_type_definition}}


 {{link|type_mark}} ::=      [§ '''6.3''']
   ''type''_name
   | ''subtype''_name


== U ==

 {{link|unbounded_array_definition}} ::=      [§ '''5.3.2.1''']
   '''array''' ( {{ref|index_subtype_definition}} { , {{ref|index_subtype_definition}} } )
   '''of''' ''element''_subtype_indication


 {{link|use_clause}} ::=      [§ '''12.4''']
   '''use''' {{ref|selected_name}} { , {{ref|selected_name}} } ;


== V ==

 {{link|variable_assignment_statement}} ::=      [§ '''10.6.1''']
   [ {{ref|label}} : ] {{ref|simple_variable_assignment}}
   | [ {{ref|label}} : ] {{ref|conditional_variable_assignment}}
   | [ {{ref|label}} : ] {{ref|selected_variable_assignment}}


 {{link|variable_declaration}} ::=      [§ '''6.4.2.4''']
   [ '''shared''' ] '''variable''' {{ref|identifier_list}} : {{ref|subtype_indication}} [ := {{ref|expression}} ] ;


 {{link|verification_unit_binding_indication}} ::=      [§ '''7.3.4''']
   '''use vunit''' {{ref|verification_unit_list}}


 {{link|verification_unit_list}} ::= ''verification_unit_''name { , ''verification_unit_''name }      [§ '''7.3.4''']


== W ==

 {{link|wait_statement}} ::=      [§ '''10.2''']
   [ {{ref|label}} : ] '''wait''' [ {{ref|sensitivity_clause}} ] [ {{ref|condition_clause}} ] [ {{ref|timeout_clause}} ] ;


 {{link|waveform}} ::=      [§ '''10.5.2.1''']
   {{ref|waveform_element}} { , {{ref|waveform_element}} }
   | '''unaffected'''


 {{link|waveform_element}} ::=      [§ '''10.5.2.2''']
   ''value''_expression [ '''after''' ''time''_expression ]
   | '''null''' [ '''after''' ''time''_expression ]


{| class=standard align=center width=80%
! [[#A|A]]
! [[#B|B]]
! [[#C|C]]
! [[#D|D]]
! [[#E|E]]
! [[#F|F]]
! [[#G|G]]
! [[#I|I]]
! [[#L|L]]
! [[#M|M]]
! [[#N|N]]
! [[#O|O]]
! [[#P|P]]
! [[#Q|Q]]
! [[#R|R]]
! [[#S|S]]
! [[#T|T]]
! [[#U|U]]
! [[#V|V]]
! [[#W|W]]
|}