%require  "3.0"
%defines 
%define parse.trace
%verbose

%define parse.error verbose
 
%{
    #include <stdio.h> 
    #include <string.h>
    #include <assert.h>
    #include "verilog_keyword.h"

    extern int yylex();
    extern int yylineno;
    extern char * yytext;

    void yyerror(const char *msg){
        printf("line %d - ERROR: %s\n", yylineno,msg);
        printf("- '%s'\n", yytext);
    }
%} 
 
%code requires{
#include "stdio.h"
#include "object.h"
#include "dlist.h"
#include "verilog_parsetree.h"
#include "verilog_root.h"
#include "verilog_module.h"
#include "verilog_keyword.h"

}

/* token types */
%union {
	HOBJECT treenode;
	char * string;
	int token;
	int operator;
	int ival;
	IDListVar list;
}

%token <string> END  ANY  NEWLINE  SPACE  TAB

%token <string> BIN_VALUE  OCT_VALUE  HEX_VALUE  DEC_VALUE  
				DEC_BASE  BIN_BASE  OCT_BASE  HEX_BASE  
				NUM_REAL  NUM_SIZE  UNSIGNED_NUMBER  
				SYSTEM_ID  SIMPLE_ID  ESCAPED_ID  DEFINE_ID  
				STRING

/* Operators Precedence */
%token <token> '@' ',' '#' '.' '=' ':' ';' '(' ')' '[' ']' '{' '}' '+' '-' '*' '/' '%' '>' '<' '!' '&' '|' '^' '~' '?' 

%token <token> ATTRIBUTE_START ATTRIBUTE_END ASL ASR LSL LSR GTE LTE L_AND L_OR L_EQ C_EQ L_NEQ C_NEQ B_EQU B_NAND B_NOR IDX_PRT_SEL

%token <token>  KW_ALWAYS  KW_AND  KW_ASSIGN  KW_AUTOMATIC  KW_BEGIN  KW_BUF  KW_BUFIF0  KW_BUFIF1  KW_CASE  KW_CASEX  
				KW_CASEZ  KW_CELL  KW_CMOS  KW_CONFIG  KW_DEASSIGN  KW_DEFAULT  KW_DEFPARAM  KW_DESIGN  KW_DISABLE  
				KW_EDGE  KW_ELSE  KW_END  KW_ENDCASE  KW_ENDCONFIG  KW_ENDFUNCTION  KW_ENDGENERATE  KW_ENDMODULE  
				KW_ENDPRIMITIVE  KW_ENDSPECIFY  KW_ENDTABLE  KW_ENDTASK  KW_EVENT  KW_FOR  KW_FORCE  KW_FOREVER  KW_FORK  
				KW_FUNCTION  KW_GENERATE  KW_GENVAR  KW_HIGHZ0  KW_HIGHZ1  KW_IF  KW_IFNONE  KW_INCDIR  KW_INCLUDE  
				KW_INITIAL  KW_INOUT  KW_INPUT  KW_INSTANCE  KW_INTEGER  KW_JOIN  KW_LARGE  KW_LIBLIST  KW_LIBRARY  
				KW_LOCALPARAM  KW_MACROMODULE  KW_MEDIUM  KW_MODULE  KW_NAN  KW_NEGEDGE  KW_NMOS  KW_NOR  KW_NOSHOWCANCELLED  
				KW_NOT  KW_NOTIF0  KW_NOTIF1  KW_OR  KW_OUTPUT  KW_PARAMETER  KW_PATHPULSE  KW_PMOS  KW_POSEDGE  KW_PRIMITIVE  
				KW_PULL0  KW_PULL1  KW_PULLDOWN  KW_PULLUP  KW_PULSESTYLE_ONEVENT  KW_PULSESTYLE_ONDETECT  KW_RCMOS  
				KW_REAL  KW_REALTIME  KW_REG  KW_RELEASE  KW_REPEAT  KW_RNMOS  KW_RPMOS  KW_RTRAN  KW_RTRANIF0  KW_RTRANIF1  
				KW_SCALARED  KW_SHOWCANCELLED  KW_SIGNED  KW_SMALL  KW_SPECIFY  KW_SPECPARAM  KW_STRONG0  KW_STRONG1  
				KW_SUPPLY0  KW_SUPPLY1  KW_TABLE  KW_TASK  KW_TIME  KW_TRAN  KW_TRANIF0  KW_TRANIF1  KW_TRI  KW_TRI0  
				KW_TRI1  KW_TRIAND  KW_TRIOR  KW_TRIREG  KW_UNSIGNED  KW_USE  KW_VECTORED  KW_WAIT  KW_WAND  KW_WEAK0  
				KW_WEAK1  KW_WHILE  KW_WIRE  KW_WOR  KW_XNOR  KW_XOR KW_NAND KW_UWIRE 
                KW_SYS_SETUP KW_SYS_HOLD KW_SYS_SETUPHOLD KW_SYS_RECOVERY KW_SYS_REMOVAL KW_SYS_RECREM KW_SYS_SKEW 
                KW_SYS_TIMESKEW KW_SYS_FULLSKEW KW_SYS_PERIOD KW_SYS_WIDTH KW_SYS_NOCHANGE 

/* Operator Precedence */


%right  '?'                 /* Lowest Precedence */
%left   L_OR
%left   L_AND
%left   '|' B_NOR
%left   B_EQU '^'
%left   B_NAND '&'
%left   L_EQ C_EQ L_NEQ C_NEQ
%left   '>' '<' GTE LTE
%left   LSL LSR ASR ASL
%left   '+' '-'
%left   '*' '/' '%'
%left   POW
%right  '!' '~'    /* Highest Precedence. */
				
%start grammar_begin

%type <ival> enable_gatetype

%type <treenode> module_identifier parameter_declaration port port_declaration port_reference
             
%type <list> attribute_instance_list module_parameter_port_list list_of_port_declarations
             list_of_ports module_item_list non_port_module_item_list module_param_list
             ports port_declarations port_expression

%type <operator> unary_operator unary_module_path_operator binary_module_path_operator

%%

/* Start variables */
grammar_begin : 
  library_text {}
| source_text {}
| {}
;

/* A.1.1 Library Source Text */

library_text : 
  library_descriptions {}
| library_text library_descriptions{}
;

library_descriptions : 
  library_declaration{}
| include_statement{}
| config_declaration{}
;

library_declaration : 
  KW_LIBRARY library_identifier file_path_specs ';'{}
| KW_LIBRARY library_identifier file_path_specs KW_INCDIR file_path_specs ';'{}
;

file_path_specs : 
  file_path_spec{}
| file_path_specs ',' file_path_spec{}
;

file_path_spec : file_path{}
;

file_path : string {}
;

include_statement : KW_INCLUDE file_path_spec ';'{}
;
   
/* A.1.2  Verilog source text. */

source_text : 
  description {
  }
| source_text description{
}
;

description : 
  module_declaration {
  }
| udp_declaration {
}
| config_declaration {
}
;

module_item_list :
    {
    }
|   module_item {
    }
|   module_item_list module_item {
    }
  ;

non_port_module_item_list :
    {
    }
|   non_port_module_item {
    }
|   non_port_module_item_list non_port_module_item {
    }
  ;

module_declaration : 
  attribute_instance_list
  module_keyword
  module_identifier
  module_parameter_port_list
  list_of_ports
  ';'
  module_item_list
  KW_ENDMODULE
{
	IVerilogRoot ** ppRoot = getVerilogRoot();
	(*ppRoot)->add_module(ppRoot, verilogparseCreateModuleDeclaration(&$1,$3,&$4,&$5,&$7));
}  

| attribute_instance_list
  module_keyword
  module_identifier
  module_parameter_port_list
  list_of_port_declarations
  ';'
  non_port_module_item_list
  KW_ENDMODULE
  {
	IVerilogRoot ** ppRoot = getVerilogRoot();
	(*ppRoot)->add_module(ppRoot, verilogparseCreateModuleDeclaration(&$1,$3,&$4,&$5,&$7));
}
;

module_keyword :
  KW_MODULE {
  }
| KW_MACROMODULE {
  }
  ;


/*
A.1.3 Module parameters and ports
*/

module_parameter_port_list  : {
}
| '#' '(' module_param_list ')'{
    $$ = $3;
}
;

module_param_list     : 
  parameter_declaration{
    dlistInit(&$$);
	dlistAppendItem(&$$, $1);
  }
| module_param_list ',' parameter_declaration{
	dlistAppendItem(&$1, $3);
	$$ = $1;
}
;

list_of_ports   : {
}
| '(' ports ')' {
    $$ = $2;
}
;

ports           : {
	dlistInit(&$$);
}
| ports ',' port{
    $$ = $1;
    dlistAppendItem(&$$,$3);
}
| port {
    dlistInit(&$$);
	dlistAppendItem(&$$,$1);
}
;

list_of_port_declarations   : 
  '(' ')'{
	dlistInit(&$$);
  }
| '(' port_declarations ')'{
    $$ = $2;
}
;

port_declarations : 
  { 
    dlistInit(&$$);
  }
| port_declarations ',' port_declaration {
    $$ = $1;
    dlistAppendItem(&$$,$3);
  }
| port_declaration {
    dlistInit(&$$);
	dlistAppendItem(&$$,$1);
  }
  ;

port            : 
  port_expression{
    //$$ = verilogparserCreatePort(NULL, &$1);
  }
| '.' port_identifier '(' port_expression ')'{
   // $$ = verilogparserCreatePort($2, &$4);
}
;

port_expression : 
	{
		dlistInit(&$$);
	}
| port_reference {
    dlistInit(&$$);
    dlistAppendItem(&$$, $1);
  }
| port_expression ',' port_reference{
    $$ = $1;
    dlistAppendItem(&$$,$3);
}
;

port_reference  : 
  port_identifier{
}
| port_identifier '[' ']' {
}
| port_identifier '[' constant_range_expression ']' {
}
;

port_declaration : 
    attribute_instance_list inout_declaration {
    }
|   attribute_instance_list input_declaration {
    }
|   attribute_instance_list output_declaration {
    }
;

/* 
A.1.4 Module Items 
*/

module_item :
    port_declaration {
    }
|   non_port_module_item {
    }
 ;

module_or_generate_item :
  attribute_instance_list module_or_generate_item_declaration {
  }
| attribute_instance_list local_parameter_declaration ';' {
  }
| attribute_instance_list parameter_override {
  }
| attribute_instance_list continuous_assign {
  }
| attribute_instance_list gate_instantiation {
  }
| attribute_instance_list udp_instantiation {
  }
| attribute_instance_list module_instantiation {
  }
| attribute_instance_list initial_construct {
  }
| attribute_instance_list always_construct {
  }
| attribute_instance_list loop_generate_construct {
  }
| attribute_instance_list conditional_generate_construct {
  }
  ;

module_or_generate_item_declaration :
    net_declaration {
    }
|   reg_declaration {
    }
|   integer_declaration {
    }
| real_declaration {
    }
| time_declaration {
    }
| realtime_declaration {
    }
| event_declaration {
    }
| genvar_declaration {
    }
| task_declaration {
    }
| function_declaration {
    }
 ;

non_port_module_item :
    module_or_generate_item {
    }
|   generate_region {
    }
| specify_block {
    }
|   attribute_instance_list parameter_declaration ';' {
    }
|   attribute_instance_list specparam_declaration {
    }
   ;

parameter_override :
    KW_DEFPARAM list_of_defparam_assignments ';' {
    }
    ;

/*
A.1.5 Configuration source text
*/
config_declaration :
    KW_CONFIG config_identifier ';' 
    design_statement KW_ENDCONFIG {
    }
|   KW_CONFIG config_identifier ';' 
    design_statement config_rule_statement KW_ENDCONFIG {
    }
 ;

design_statement : KW_DESIGN design_cell_list ';' {
}
;

design_cell_list :
  {
  }
|  design_cell_list design_cell {
  } 
|  design_cell {
 }
 ;
 
design_cell :
  cell_identifier {
  }
| library_identifier '.' cell_identifier {
  }
  ;

config_rule_statement :
    default_clause liblist_clause ';' {
    }
|   inst_clause liblist_clause ';' {
    }
|   inst_clause use_clause ';' {
    }
|   cell_clause liblist_clause ';' {
    }
|   cell_clause use_clause ';' {
    }
 ;

default_clause :
  KW_DEFAULT {
  }
  ;

inst_clause :
    KW_INSTANCE inst_name {
    }
  ;

inst_name :
    topmodule_identifier {
    }
|   inst_name '.' instance_identifier {
    }
  ;

cell_clause : 
    KW_CELL cell_identifier {
    }
|   KW_CELL library_identifier '.' cell_identifier {
    }
 ;

liblist_clause :
    KW_LIBLIST {
    }
|   KW_LIBLIST library_identifier {
    }
 ;

use_clause :
    KW_USE cell_identifier {
    }
|   KW_USE cell_identifier ':' KW_CONFIG {
    }
|   KW_USE library_identifier '.' cell_identifier {
    }
|   KW_USE library_identifier '.' cell_identifier ':' KW_CONFIG {
    }
  ;

/*
A.2 Declarations
A.2.1 Declaration types
A.2.1.1 Module parameter declarations
*/

signed_option: 
 {
 }
| KW_SIGNED {
}
;

range_option: 
 {
 }
| range {
}
;

local_parameter_declaration :
    KW_LOCALPARAM signed_option range_option list_of_param_assignments {
    }
|   KW_LOCALPARAM parameter_type list_of_param_assignments{
    }
 ;

parameter_declaration :
    KW_PARAMETER signed_option range_option list_of_param_assignments {
    }
|   KW_PARAMETER parameter_type list_of_param_assignments {
    }
;

specparam_declaration : 
    KW_SPECPARAM range_option list_of_specparam_assignments ';' {
    }
   ;

parameter_type :
    KW_INTEGER {
    }
|   KW_REAL {
    } 
|   KW_REALTIME {
    }
|   KW_TIME {
    }
 ;

/*
A.2.1.2 Port declarations
*/

net_type_option :
  {
  }
| net_type {
  }
;

inout_declaration :
    KW_INOUT net_type_option signed_option range_option 
    list_of_port_identifiers {
    }
  ;

input_declaration :
    KW_INPUT net_type_option signed_option range_option 
    list_of_port_identifiers {
    }
  ;

output_declaration :
    KW_OUTPUT net_type_option signed_option range_option 
    list_of_port_identifiers {
    }
|   KW_OUTPUT KW_REG signed_option range_option
    list_of_variable_port_identifiers {
    }
|   KW_OUTPUT output_variable_type 
    list_of_variable_port_identifiers {
    }
  ;

/*
A.2.1.3 Type declarations
*/
event_declaration :
    KW_EVENT list_of_event_identifiers ';' {
    }
 ;

integer_declaration : KW_INTEGER list_of_variable_identifiers ';' {
    }
  ;
delay3_option: 
    {
    }
|   delay3 {
    }
  ;

drive_strength_option :
    {
    }
|   drive_strength {
    }
  ;

vectored_option :
    {
    }
|   KW_VECTORED {
    }
  ;

scalared_option :
    {
    }
|   KW_SCALARED {
    }
 ;

charge_strength_option :
    {
    }
|   charge_strength {
    }
 ;

vectored_or_scalared_option : 
    {
    } 
|   KW_VECTORED {
    }
|   KW_SCALARED {
    }
 ;

net_declaration :
    net_type signed_option
    delay3_option list_of_net_identifiers ';' {
    }
|   net_type drive_strength_option signed_option
    delay3_option list_of_net_decl_assignments ';' {
    }
|   net_type vectored_option signed_option
    range delay3_option list_of_net_identifiers ';' {
    }
|   net_type scalared_option signed_option
    range delay3_option list_of_net_identifiers ';' {
    }
|   net_type drive_strength_option vectored_option 
    scalared_option signed_option
    range delay3_option list_of_net_decl_assignments ';' {
    }
|   KW_TRIREG charge_strength_option signed_option
    delay3_option list_of_net_identifiers ';'
|   KW_TRIREG drive_strength_option signed_option
    delay3_option list_of_net_decl_assignments ';' {
    }
|   KW_TRIREG charge_strength_option vectored_or_scalared_option signed_option
    range delay3_option list_of_net_identifiers ';' {
    }
|   KW_TRIREG drive_strength_option vectored_or_scalared_option signed_option
    range delay3_option list_of_net_decl_assignments ';' {
    }
 ;

real_declaration :
    KW_REAL list_of_real_identifiers ';' {
    }
  ;

realtime_declaration : 
    KW_REALTIME list_of_real_identifiers ';' {
    }
  ;

reg_declaration :
    KW_REG signed_option range_option
    list_of_variable_identifiers ';' {
    }
  ;

time_declaration : 
    KW_TIME list_of_variable_identifiers ';' {
    }
  ;

/*
A.2.2 Declaration data types
A.2.2.1 Net and variable types
*/
net_type :
    KW_SUPPLY0 {
    }
|   KW_SUPPLY1 {
    }
|   KW_TRI {
    } 
|   KW_TRIAND  {
    }
|   KW_TRIOR  {
    }
|   KW_TRI0  {
    }
|   KW_TRI1 {
    }
|   KW_UWIRE  {
    }
|   KW_WIRE  {
    }
|   KW_WAND  {
    }
|   KW_WOR {
    }
  ;

output_variable_type : 
    KW_INTEGER  {
    }
|   KW_TIME {
    }
 ;

dimension_list :
    {
    }
| dimension_list dimension {
    }
| dimension {
}
;

real_type :
    real_identifier dimension_list {
    }
|   real_identifier '=' constant_expression {
    }
 ;
variable_type :
    variable_identifier dimension_list {
    }
|   variable_identifier '=' constant_expression {
    }
 ;
 
/*
A.2.2.2 Strengths 
*/

drive_strength :
    '(' strength0 ',' strength1 ')' {
    }
|   '(' strength1 ',' strength0 ')' {
    }
|   '(' strength0 ',' KW_HIGHZ1 ')' {
    }
|   '(' strength1 ',' KW_HIGHZ0 ')' {
    }
|   '(' KW_HIGHZ0 ',' strength1 ')' {
    }
|   '(' KW_HIGHZ1 ',' strength0 ')' {
    }
  ;
strength0 : 
    KW_SUPPLY0  {
    }
|   KW_STRONG0  {
    }
|   KW_PULL0  {
    }
|   KW_WEAK0 {
    }
 ;

strength1 : 
    KW_SUPPLY1  {
    }
|   KW_STRONG1  {
    }
|   KW_PULL1  {
    }
|   KW_WEAK1 {
    }
  ;

charge_strength : 
    '(' KW_SMALL ')' {
    } 
|   '(' KW_MEDIUM ')'  {
    }
|   '(' KW_LARGE ')' {
    }
 ;

/*
A.2.2.3 Delays
*/

delay3 :
    '#' delay_value {
    }
|   '#' '(' mintypmax_expression ')' {
    }
|   '#' '(' mintypmax_expression ',' mintypmax_expression ')' {
    }
|   '#' '(' mintypmax_expression ',' mintypmax_expression ',' mintypmax_expression ')' {
    }
 ;

delay2 :
    '#' delay_value
|   '#' '(' mintypmax_expression ')' {
    }
|   '#' '(' mintypmax_expression ',' mintypmax_expression ')' {
    }
 ;

delay_value :
    unsigned_number {
    }
|   NUM_REAL {
    }
|   identifier {
    }
 ;

/*
A.2.3 Declaration lists
*/
list_of_defparam_assignments :
    defparam_assignment {
    }
|   list_of_defparam_assignments  ',' defparam_assignment {
    }
 ;

list_of_dimensions:
    dimension {
    }
|   list_of_dimensions  ',' dimension {
    }
 ;

list_of_event_identifiers : 
    event_identifier list_of_dimensions {
    }
|   list_of_event_identifiers ',' event_identifier list_of_dimensions {
    }
  ;

list_of_net_decl_assignments :
    net_decl_assignment {
    }
|   list_of_net_decl_assignments  ',' net_decl_assignment {
    }
 ;
 
dimension_list :
    {
    }
|   dimension {
    }
|   dimension_list dimension {
    }
  ;

list_of_net_identifiers : 
    net_identifier dimension_list {
    }
|   list_of_net_identifiers  ',' net_identifier dimension_list {
    }
  ;

list_of_event_identifiers : 
    net_identifier list_of_dimensions {
    }
|   list_of_event_identifiers ',' net_identifier list_of_dimensions {
    }
  ;

list_of_param_assignments :
    param_assignment {
    }
|   list_of_param_assignments  ',' param_assignment {
    }
 ;
 

list_of_port_identifiers :
    port_identifier {
    }
|   list_of_port_identifiers  ',' port_identifier {
    }
 ;
 
list_of_real_identifiers :
    real_type {
    }
|   list_of_real_identifiers  ',' real_type {
    }
 ;
 

list_of_specparam_assignments :
    specparam_assignment {
    }
|   list_of_specparam_assignments  ',' specparam_assignment {
    }
 ;
 
list_of_variable_identifiers :
    variable_type {
    }
|   list_of_variable_identifiers  ',' variable_type {
    }
 ;
 
port_ident :
    port_identifier {
    }
|   port_identifier '=' constant_expression {
    }
 ;

list_of_variable_port_identifiers :
    port_ident {
    }
|   list_of_variable_port_identifiers  ',' port_ident {
    }
 ;

/*
A.2.4 Declaration assignments
*/

defparam_assignment : 
    hierarchical_parameter_identifier '=' constant_mintypmax_expression {
    }
  ;

net_decl_assignment : 
    net_identifier '=' expression {
    }
  ;

param_assignment : 
    parameter_identifier '=' constant_mintypmax_expression {
    }
  ;

specparam_assignment :
    specparam_identifier '=' constant_mintypmax_expression {
    }
|    pulse_control_specparam {
    }
 ;

/* 
    PATHPULSE$specify_input_terminal_descriptor$specify_output_terminal_descriptor 
    must be:
    1.PATHPULSE$identinput$identoutput
    1.PATHPULSE$identinput$identoutput '[' constant_range_expression ']'
    1.PATHPULSE$identinput '[' constant_range_expression ']' $identoutput
    1.PATHPULSE$identinput '[' constant_range_expression ']' $identoutput '[' constant_range_expression ']'
*/

pulse_control_specparam_lvalue :
    SIMPLE_ID /* PATHPULSE$identinput$identoutput */ {
    }
|   SIMPLE_ID /* PATHPULSE$identinput$identoutput  '[' constant_range_expression ']' */
    '[' constant_range_expression ']'  {
    }
|   SIMPLE_ID /* PATHPULSE$identinput '[' constant_range_expression ']' $identoutput*/
    '[' constant_range_expression ']' 
    SYSTEM_ID {
    }
|   SIMPLE_ID /* PATHPULSE$identinput '[' constant_range_expression ']'  $identoutput '[' constant_range_expression ']'*/
    '[' constant_range_expression ']' 
    SYSTEM_ID
    '[' constant_range_expression ']' {
    }
  ;
    
pulse_control_specparam : 
    KW_PATHPULSE '=' '(' reject_limit_value ')' {
    }
|   KW_PATHPULSE '=' '(' reject_limit_value ',' error_limit_value ')' {
    }
|   pulse_control_specparam_lvalue
    '=' '(' reject_limit_value ')' {
    }
|   pulse_control_specparam_lvalue
     '=' '(' reject_limit_value ',' error_limit_value ')' {
    }
  ;


error_limit_value : 
    limit_value {
    }
  ;

reject_limit_value : 
    limit_value {
    }
  ;

limit_value : 
    constant_mintypmax_expression {
    }
 ;

/*
A.2.5 Declaration ranges
*/
dimension : 
    '[' dimension_constant_expression ':' dimension_constant_expression ']' {
    }
 ;

range : '[' msb_constant_expression ':' lsb_constant_expression ']' {
    }
  ;

/*
A.2.6 Function declarations
*/
automatic_option :
    {
    }
|   KW_AUTOMATIC { 
    }
  ;

function_range_or_type_option:
    {
    }
|   function_range_or_type {
    }
  ;

function_item_declaration_list:
    function_item_declaration {
    }
|   function_item_declaration_list function_item_declaration {
    }
 ;

block_item_declaration_list:
    {
    }
|   block_item_declaration {
    }
|   block_item_declaration_list block_item_declaration {
    }
 ;

function_range_or_type_option :
    {
    }
|   function_range_or_type {
    }
  ;

function_declaration :
    KW_FUNCTION automatic_option function_range_or_type_option function_identifier ';'
    function_item_declaration_list
    function_statement
    KW_ENDFUNCTION {
    }
|   KW_FUNCTION automatic_option function_range_or_type_option function_identifier '(' function_port_list ')' ';'
    block_item_declaration_list   
    function_statement
    KW_ENDFUNCTION {
    }
 ;

function_item_declaration :
    block_item_declaration
|   attribute_instance_list tf_input_declaration ';' {
    }
 ;

function_port_list :
    attribute_instance_list tf_input_declaration {
    }
|   function_port_list attribute_instance_list tf_input_declaration {
    }
  ;

function_range_or_type :
    signed_option range_option {
    }
|   KW_INTEGER {
    }
|   KW_REAL {
    }
|   KW_REALTIME {
    }
| KW_TIME {
    }
  ;

/*
A.2.7 Task declarations
*/
task_item_declaration_list :
    {
    }
|   task_item_declaration_list task_item_declaration {
    }
|   task_item_declaration {
    }
 ;

task_port_list_option:
    {
    }
|   task_port_list {
    }
  ;

task_declaration :
    KW_TASK automatic_option task_identifier ';'
    task_item_declaration_list
    statement_or_null
    KW_ENDTASK {
    }
|   KW_TASK automatic_option task_identifier '(' task_port_list_option ')' ';'
    block_item_declaration_list
    statement_or_null
    KW_ENDTASK {
    }
 ;

task_item_declaration :
    block_item_declaration {
    }
|   attribute_instance_list tf_input_declaration ';' {
    }
|   attribute_instance_list tf_output_declaration ';' {
    }
|   attribute_instance_list tf_inout_declaration ';' {
    }
  ;

task_port_list :
    task_port_item {
    }
|   task_port_list ',' task_port_item {
    }
 ;

task_port_item :
    attribute_instance_list tf_input_declaration {
    }
|   attribute_instance_list tf_output_declaration {
    }
|   attribute_instance_list tf_inout_declaration {
    }
  ;

reg_option :
    {
    }
|   KW_REG {
    }
  ;   

tf_input_declaration :
    KW_INPUT reg_option signed_option range_option list_of_port_identifiers {
    }
|   KW_INPUT task_port_type list_of_port_identifiers {
    }
  ;

tf_output_declaration :
    KW_OUTPUT reg_option signed_option range_option list_of_port_identifiers {
    }
|   KW_OUTPUT task_port_type list_of_port_identifiers {
    }
  ;

tf_inout_declaration :
    KW_INOUT reg_option signed_option range_option list_of_port_identifiers {
    }
|   KW_INOUT task_port_type list_of_port_identifiers {
    }
  ;

task_port_type :
    KW_INTEGER  {
    }
|   KW_REAL {
    }
|   KW_REALTIME {
    }
|   KW_TIME{
    }
  ;

/*
A.2.8 Block item declarations
*/
block_item_declaration :
    attribute_instance_list  KW_REG signed_option range_option list_of_block_variable_identifiers ';' {
    }
|   attribute_instance_list  KW_INTEGER list_of_block_variable_identifiers ';' {
    }
|   attribute_instance_list  KW_TIME list_of_block_variable_identifiers ';' {
    }
|   attribute_instance_list  KW_REAL list_of_block_real_identifiers ';' {
    }
|   attribute_instance_list  KW_REALTIME list_of_block_real_identifiers ';' {
    }
|   attribute_instance_list  event_declaration {
    }
|   attribute_instance_list  local_parameter_declaration ';' {
    }
|   attribute_instance_list  parameter_declaration ';' {
    }
  ;

list_of_block_variable_identifiers :
    block_variable_type {
    }
|   list_of_block_variable_identifiers  ',' block_variable_type {
    }
  ;

list_of_block_real_identifiers : 
    block_real_type {
    } 
|   list_of_block_real_identifiers ',' block_real_type {
    }
  ;

block_variable_type : 
    variable_identifier dimension_list {
    }
 ;

block_real_type : 
    real_identifier dimension_list {
    }
  ;

/*
A.3 Primitive instances
A.3.1 Primitive instantiation and instances
*/

cmos_switch_instance_list:
    cmos_switch_instance {
    }
|   cmos_switch_instance_list ',' cmos_switch_instance {
    }
  ;

enable_gate_instance_list:
    enable_gate_instance {
    }
|   enable_gate_instance_list ',' enable_gate_instance {
    }
  ;

mos_switch_instance_list:
    mos_switch_instance {
    }
|   mos_switch_instance_list ',' mos_switch_instance {
    }
  ;

n_input_gate_instance_list:
    n_input_gate_instance {
    }
|   n_input_gate_instance_list ',' n_input_gate_instance {
    }
  ;

n_output_gate_instance_list:
    n_output_gate_instance {
    }
|   n_output_gate_instance_list ',' n_output_gate_instance {
    }
  ;

pass_enable_switch_instance_list:
    pass_enable_switch_instance {
    }
|   pass_enable_switch_instance_list ',' pass_enable_switch_instance {
    }
  ;

pass_switch_instance_list:
    pass_switch_instance {
    }
|   pass_switch_instance_list ',' pass_switch_instance {
    }
  ;

pulldown_strength_option :
    {
    }
|   pulldown_strength {
    }
  ;

pullup_strength_option :
    {
    }
|   pullup_strength {
    }
  ;

pull_gate_instance_list:
    pull_gate_instance {
    }
|   pull_gate_instance_list ',' pull_gate_instance {
    }
  ;

delay2_option :
    {
    }
|   delay2 {
    }
  ;

gate_instantiation :
    cmos_switchtype delay3_option cmos_switch_instance_list ';' {
    }
|   enable_gatetype drive_strength_option delay3_option enable_gate_instance_list ';' {
    }
|   mos_switchtype delay3_option mos_switch_instance_list ';' {
    }
|   n_input_gatetype drive_strength_option delay2_option n_input_gate_instance_list ';' {
    }
|   n_output_gatetype drive_strength_option delay2_option n_output_gate_instance_list ';' { 
    }
|   pass_en_switchtype delay2_option pass_enable_switch_instance_list ';' {
    }
|   pass_switchtype pass_switch_instance_list ';' {
    }
|   KW_PULLDOWN pulldown_strength_option pull_gate_instance_list ';' {
    }
|   KW_PULLUP pullup_strength_option pull_gate_instance_list ';' {
    }
 ;

name_of_gate_instance_option :
    {
    }
|   name_of_gate_instance {
    }
  ;


input_terminal_list:
    input_terminal {
    }
|   input_terminal_list ',' input_terminal {
    }
  ;

output_terminal_list:
    output_terminal {
    }
|   output_terminal_list ',' output_terminal {
    }
  ;

cmos_switch_instance : 
    name_of_gate_instance_option '(' output_terminal ',' input_terminal ',' ncontrol_terminal ',' pcontrol_terminal ')' {
    }
 ;

enable_gate_instance : 
    name_of_gate_instance_option '(' output_terminal ',' input_terminal ',' enable_terminal ')' {
    }
  ;

mos_switch_instance : 
    name_of_gate_instance_option '(' output_terminal ',' input_terminal ',' enable_terminal ')' {
    }
  ;

n_input_gate_instance : 
    name_of_gate_instance_option '(' output_terminal ',' input_terminal_list ')' {
    }
  ;

n_output_gate_instance : 
    name_of_gate_instance_option '(' output_terminal_list ',' input_terminal ')' {
    }
  ;

pass_switch_instance : 
    name_of_gate_instance_option '(' inout_terminal ',' inout_terminal ')' {
    }
  ;

pass_enable_switch_instance : 
    name_of_gate_instance_option '(' inout_terminal ',' inout_terminal ',' enable_terminal ')' {
    }
  ;

pull_gate_instance : 
    name_of_gate_instance_option '(' output_terminal ')' {
    }
  ;

name_of_gate_instance : 
    gate_instance_identifier range_option {
    }
  ;

/*
A.3.2 Primitive strengths
*/

pulldown_strength :
    '(' strength0 ',' strength1 ')' {
    }
|   '(' strength1 ',' strength0 ')' {
    }
|   '(' strength0 ')' {
    }
  ;

pullup_strength :
    '(' strength0 ',' strength1 ')' {
    }
|   '(' strength1 ',' strength0 ')' {
    }
|   '(' strength1 ')' {
    }
  ;

/*
A.3.3 Primitive terminals
*/
enable_terminal : 
    expression {
    }
  ;

inout_terminal : 
    net_lvalue {
    }
  ;

input_terminal : 
    expression {
    }
  ;

ncontrol_terminal : 
    expression {
    }
  ;

output_terminal : 
    net_lvalue {
    }
  ;

pcontrol_terminal : 
    expression {
    }
  ;

/*
A.3.4 Primitive gate and switch types
*/
cmos_switchtype : 
    KW_CMOS  {
    }
|   KW_RCMOS {
    }
  ;
enable_gatetype : 
    KW_BUFIF0  {
    }
|   KW_BUFIF1 {
    }
|   KW_NOTIF0  {
    }
|   KW_NOTIF1 {
    }
  ;

mos_switchtype : 
    KW_NMOS  {
    }
|   KW_PMOS  {
    }
|   KW_RNMOS  {
    }
|   KW_RPMOS {
    }
  ;

n_input_gatetype : 
    KW_AND  {
    }
|   KW_NAND  {
    }
|   KW_OR  {
    }
|   KW_NOR  {
    }
|   KW_XOR  {
    }
|   KW_XNOR {
    }
  ;

n_output_gatetype : 
    KW_BUF {
    } 
|   KW_NOT {
    }
  ;

pass_en_switchtype : 
    KW_TRANIF0 {
    }
|   KW_TRANIF1 {
    }
|   KW_RTRANIF1 {
    }
|   KW_RTRANIF0 {
    }
  ;

pass_switchtype : 
    KW_TRAN  {
    }
|   KW_RTRAN {
    }
  ;

/*
A.4 Module instantiation and generate construct
A.4.1 Module instantiation
*/
parameter_value_assignment_option :
    {
    }
| parameter_value_assignment {
    }
 ;

module_instance_list:
    module_instance {
    }
|   module_instance_list ',' module_instance {
    }
  ;

module_instantiation :
    module_identifier parameter_value_assignment_option module_instance_list ';' {
    }
 ;

parameter_value_assignment : 
    '#' '(' list_of_parameter_assignments ')' {
    }
  ;

ordered_parameter_assignment_list:
    ordered_parameter_assignment {
    }
|   ordered_parameter_assignment_list ',' ordered_parameter_assignment {
    }
  ;

named_parameter_assignment_list:
    named_parameter_assignment {
    }
|   named_parameter_assignment_list ',' named_parameter_assignment {
    }
  ;

list_of_parameter_assignments :
    ordered_parameter_assignment_list {
    }
|   named_parameter_assignment_list {
    }
  ;

ordered_parameter_assignment : 
    expression {
    }
  ;

mintypmax_expression_option:
    {
    }
|   mintypmax_expression {
    }
  ;

named_parameter_assignment : 
    '.' parameter_identifier '(' mintypmax_expression_option ')' {
    }
  ;

list_of_port_connections_option:
    {
    }
|   list_of_port_connections {
    }
  ;

module_instance : 
    name_of_module_instance '(' list_of_port_connections_option ')' {
    }
  ;

name_of_module_instance : 
    module_instance_identifier range_option {
    }
  ;

ordered_port_connection_list:
    ordered_port_connection {
    }
|   ordered_port_connection_list ',' ordered_port_connection {
    }
  ;

named_port_connection_list:
    named_port_connection {
    }
|   named_port_connection_list ',' named_port_connection {
    }
  ;


list_of_port_connections :
    ordered_port_connection_list {
    }
|   named_port_connection_list {
    }
  ;

expression_option:
    {
    }
|   expression {
    }
  ;

ordered_port_connection : 
    attribute_instance_list expression_option {
    }
  ;

named_port_connection : 
    attribute_instance_list '.' port_identifier '(' expression_option ')' {
    }
  ;

/*
A.4.2 Generate construct
*/

module_or_generate_item_list:
    {
    }
|   module_or_generate_item {
    }
|   module_or_generate_item_list  module_or_generate_item {
    }
  ;


generate_region :
    KW_GENERATE module_or_generate_item_list KW_ENDGENERATE {
    }
  ;

genvar_declaration : 
    KW_GENVAR list_of_genvar_identifiers ';' {
    }
  ;

list_of_genvar_identifiers :
    genvar_identifier  {
    }
|   list_of_genvar_identifiers ',' genvar_identifier {
    }
  ;

loop_generate_construct :
    KW_FOR '(' genvar_initialization ';' genvar_expression ';' genvar_iteration ')'
    generate_block {
    }
  ;

genvar_initialization :
    genvar_identifier '=' constant_expression {
    }
  ;

genvar_expression :
    genvar_primary {
    }
|   unary_operator attribute_instance_list genvar_primary {
    }
|   genvar_expression binary_operator attribute_instance_list genvar_expression {
    }
|   genvar_expression '?' attribute_instance_list genvar_expression ':' genvar_expression {
    }
  ;

genvar_iteration :
    genvar_identifier '=' genvar_expression {
    }
  ;

genvar_primary :
    constant_primary {
    }
|   genvar_identifier {
    }
  ;

conditional_generate_construct :
    if_generate_construct {
    }
|   case_generate_construct {
    }
  ;

if_generate_construct :
    KW_IF '(' constant_expression ')' generate_block_or_null {
    }
|   KW_IF '(' constant_expression ')' generate_block_or_null KW_ELSE generate_block_or_null {
    }
  ;


case_generate_item_list:
    case_generate_item {
    }
|   case_generate_item_list  case_generate_item {
    }
  ;

case_generate_construct :
    KW_CASE '(' constant_expression ')' case_generate_item_list KW_ENDCASE {
    }
  ;

constant_expression_list:
    constant_expression {
    }
|   constant_expression_list  constant_expression {
    }
  ;

case_generate_item :
    constant_expression_list ':' generate_block_or_null {
    }
|   KW_DEFAULT generate_block_or_null {
    }
|   KW_DEFAULT ':' generate_block_or_null {
    }
  ;

module_or_generate_item_list :
    {
    }
|   module_or_generate_item_list module_or_generate_item {
    }
|   module_or_generate_item {   
    }
  ;

generate_block :
    module_or_generate_item {
    }
|   KW_BEGIN  ':' generate_block_identifier module_or_generate_item_list KW_END {
    }
|   KW_BEGIN module_or_generate_item_list KW_END {
    }
  ;

generate_block_or_null :
    generate_block {
    }
|   ';' {
    }
  ;

/*
A.5 UDP declaration and instantiation
A.5.1 UDP declaration
*/

udp_port_declaration_list :
    udp_port_declaration_list udp_port_declaration {
    }
|   udp_port_declaration {   
    }
  ;

udp_declaration :
    attribute_instance_list KW_PRIMITIVE udp_identifier '(' udp_port_list ')' ';'
    udp_port_declaration_list 
    udp_body
    KW_ENDPRIMITIVE {
    }
|   attribute_instance_list KW_PRIMITIVE udp_identifier '(' udp_declaration_port_list ')' ';'
    udp_body
    KW_ENDPRIMITIVE {
    }
  ;

/*
A.5.2 UDP ports
*/

udp_port_list : 
    output_port_identifier ',' input_port_identifier {
    }
|   udp_port_list ',' input_port_identifier {
    }
  ;

udp_declaration_port_list :
    udp_output_declaration ',' udp_input_declaration{
    } 
|   udp_declaration_port_list ',' udp_input_declaration {
    }
  ;

udp_port_declaration :
    udp_output_declaration ';' {
    }
|   udp_input_declaration ';' {
    }
|   udp_reg_declaration ';' {
    }
  ;

udp_output_declaration :
    attribute_instance_list KW_OUTPUT port_identifier {
    }
|   attribute_instance_list KW_OUTPUT KW_REG port_identifier {
    }
|   attribute_instance_list KW_OUTPUT KW_REG port_identifier '=' constant_expression {
    }
  ;

udp_input_declaration : 
    attribute_instance_list KW_INPUT list_of_port_identifiers {
    }
  ;

udp_reg_declaration : 
    attribute_instance_list KW_REG variable_identifier {
    }
  ;

/*
A.5.3 UDP body
*/

udp_body :
    combinational_body  {
    }
|   sequential_body {
    }
  ;

combinational_entry_list :
    combinational_entry {
    } 
|   combinational_entry_list  combinational_entry {
    }
  ;

combinational_body : 
    KW_TABLE combinational_entry_list KW_ENDTABLE {
    }
  ;

combinational_entry : 
    level_input_list ':' output_symbol ';' {
    }
  ;

sequential_entry_list :
    sequential_entry {
    } 
|   sequential_entry_list  sequential_entry {
    }
  ;

sequential_body : 
    KW_TABLE sequential_entry_list KW_ENDTABLE {
    }
|   udp_initial_statement KW_TABLE sequential_entry_list KW_ENDTABLE {
    }
  ;

udp_initial_statement : 
    KW_INITIAL output_port_identifier '=' init_val ';' {
    }
  ;

init_val : 
    number {
    }
  ;
  /* 1'b0 | 1'b1 | 1'bx | 1'bX | 1'B0 | 1'B1 | 1'Bx | 1'BX | 1 | 0 */

sequential_entry : 
    seq_input_list ':' current_state ':' next_state ';' {
    }
  ;
seq_input_list : 
    level_input_list {
    }
|   edge_input_list {
    }
  ;

level_input_list : 
    level_symbol {
    }
| level_input_list level_symbol {
    }
  ;

level_symbol_list :
    {
    }
|   level_symbol {
    }
|   level_symbol_list level_symbol {
    }
  ;

edge_input_list : 
    level_symbol_list edge_indicator level_symbol_list {
    }
  ;

edge_indicator : 
    '(' level_symbol level_symbol ')'  {
    }
| edge_symbol {
    }
  ;

current_state : 
    level_symbol {
    }
  ;

next_state : 
    output_symbol  {
    }
|   '-' {
    }
  ;


output_symbol : 
    unsigned_number {
    }
|   '?'   {
    }
|   SIMPLE_ID {
    }
  ;

level_symbol :
    unsigned_number {
    }
|   '?' {
    }
|   SIMPLE_ID {
    }
 ;

edge_symbol : /* can be r,f,p,n or star in any case. */
    SIMPLE_ID {
    }
|   '*' {
    }
  ;

/*
fixed me!
output_symbol ::= 0 | 1 | x | X
level_symbol ::= 0 | 1 | x | X | ? | b | B
edge_symbol ::= r | R | f | F | p | P | n | N | *
*/

/*
A.5.4 UDP instantiation
*/

udp_instance_list :
    udp_instance {
    }
|   udp_instance_list ',' udp_instance {
    }
  ;


udp_instantiation : 
    udp_identifier drive_strength_option delay2_option
    udp_instance_list ';' {
    }
  ;

input_terminal_list :
    input_terminal {
    }
|   input_terminal_list ',' input_terminal {
    }
  ;


udp_instance : 
    name_of_udp_instance '(' output_terminal ',' input_terminal_list ')' {
    }
|   '(' output_terminal ',' input_terminal_list ')' {
    }
  ;

name_of_udp_instance : 
    udp_instance_identifier range_option {
    }
  ;

/*
A.6 Behavioral statements
A.6.1 Continuous assignment statements
*/
continuous_assign : 
    KW_ASSIGN drive_strength_option delay3_option list_of_net_assignments ';' {
    }
  ;

list_of_net_assignments : 
    net_assignment {
    }
|   list_of_net_assignments ',' net_assignment {
    }
  ;

net_assignment : 
    net_lvalue '=' expression {
    }
  ;

/*
A.6.2 Procedural blocks and assignments
*/
initial_construct :
    KW_INITIAL statement {
    }
  ;

always_construct : 
    KW_ALWAYS statement {
    }
  ;

delay_or_event_control_option :
    {
    }
|   delay_or_event_control {
    }
  ;

blocking_assignment : 
    variable_lvalue '=' expression {
    }
|   variable_lvalue '=' delay_or_event_control_option  expression {
    }
  ;

nonblocking_assignment : 
    variable_lvalue LTE delay_or_event_control_option expression {
    }
  ;
procedural_continuous_assignments :
    KW_ASSIGN variable_assignment {
    }
|   KW_DEASSIGN variable_lvalue {
    }
|   KW_FORCE variable_assignment {
    }
|   KW_FORCE net_assignment {
    }
|   KW_RELEASE variable_lvalue {
    }
|   KW_RELEASE net_lvalue {
    }
  ;

variable_assignment : 
    variable_lvalue '=' expression {
    }
  ;

/*
A.6.3 Parallel and sequential blocks
*/
block_item_declaration_list:
    {
    }
|   block_item_declaration {
    }
|   block_item_declaration_list block_item_declaration {
    }
  ;

statement_list:
    {
    }
|   statement {
    }
|   statement_list statement {
    }
  ;

par_block : 
    KW_FORK statement_list KW_JOIN {
    }
|   KW_FORK ':' block_identifier block_item_declaration_list statement_list KW_JOIN {
    }
  ;

seq_block : 
    KW_BEGIN statement_list KW_END {
    }
|   KW_BEGIN  ':' block_identifier block_item_declaration_list statement_list KW_END {
    }
  ;

/*
A.6.4 Statements
*/
statement :
    attribute_instance_list blocking_assignment ';' {
    }
|   attribute_instance_list case_statement {
    }
|   attribute_instance_list conditional_statement {
    }
|   attribute_instance_list disable_statement {
    }
|   attribute_instance_list event_trigger {
    }
|   attribute_instance_list loop_statement {
    }
|   attribute_instance_list nonblocking_assignment ';' {
    }
|   attribute_instance_list par_block {
    }
|   attribute_instance_list procedural_continuous_assignments ';' {
    }
|   attribute_instance_list procedural_timing_control_statement {
    }
|   attribute_instance_list seq_block {
    }
|   attribute_instance_list system_task_enable {
    }
|   attribute_instance_list task_enable {
    }
|   attribute_instance_list wait_statement {
    }
  ;

statement_or_null :
    statement {
    }
|   attribute_instance_list ';' {
    }
  ;

function_statement : 
    statement {
    }
  ;

/*
A.6.5 Timing control statements
*/
delay_control :
    '#' delay_value {
    }
|   '#' '(' mintypmax_expression ')' {
    }
  ;

delay_or_event_control :
    delay_control {
    }
|   event_control {
    }
|   KW_REPEAT '(' expression ')' event_control {
    }
  ;

disable_statement :
    KW_DISABLE hierarchical_task_identifier ';' {
    }
|   KW_DISABLE hierarchical_block_identifier ';' {
    }
  ;

event_control :
    '@' hierarchical_event_identifier {
    }
|   '@' '(' event_expression ')' {
    }
|   '@' '*' {
    }
|   '@' '(' '*' ')' {
    }
  ;

script_list :
    {
    }
| '['expression ']' {
    }
|script_list '['expression ']' {
    }
  ;

event_trigger :
    '-' '>' hierarchical_event_identifier script_list ';' {
    }
  ;

event_expression :
    expression {
    }
|   KW_POSEDGE expression {
    }
|   KW_NEGEDGE expression {
    }
|   event_expression KW_OR event_expression {
    }
|   event_expression ',' event_expression {
    }
  ;

procedural_timing_control :
    delay_control {
    }
|   event_control {
    }
  ;

procedural_timing_control_statement :
    procedural_timing_control statement_or_null {
    }
  ;

wait_statement :
    KW_WAIT '(' expression ')' statement_or_null {
    }
  ;

/*
A.6.6 Conditional statements
*/
conditional_statement :
    KW_IF '(' expression ')'
    statement_or_null KW_ELSE statement_or_null {
    }
|   KW_IF '(' expression ')'
    statement_or_null {
    }
|   if_else_if_statement {
    }
  ;

else_if_list:
    {
    } 
|   KW_ELSE KW_IF '(' expression ')' statement_or_null {
    }
|   else_if_list KW_ELSE KW_IF '(' expression ')' statement_or_null {
    }
  ;

if_else_if_statement :
    KW_IF '(' expression ')' statement_or_null
    else_if_list
    KW_ELSE statement_or_null {
    }
|   KW_IF '(' expression ')' statement_or_null
    else_if_list {
    }
  ;

/*
A.6.7 Case statements
*/
case_item_list :
    case_item {
    }
|   case_item_list case_item {
    }
  ;

case_type:
    KW_CASE {
    }
|   KW_CASEZ {
    }
|   KW_CASEX {
    }
  ;

case_statement :
    case_type '(' expression ')' case_item_list KW_ENDCASE {
    }
  ;

expression_list :
    expression {
    }
|   expression_list ',' expression {
    }
  ;

case_item :
    expression_list ':' statement_or_null {
    }
|   KW_DEFAULT ':' statement_or_null {
    }
|   KW_DEFAULT statement_or_null {
    }
  ;

/*
A.6.8 Looping statements
*/
loop_statement :
    KW_FOREVER statement {
    }
|   KW_REPEAT '(' expression ')' statement {
    }
|   KW_WHILE '(' expression ')' statement {    
    }
|   KW_FOR '(' variable_assignment ';' expression ';' variable_assignment ')' statement {
    }
  ;

/*
A.6.9 Task enable statements
*/
expression_or_null_list :
    {
    }
|   expression {
    }
|   expression_or_null_list ',' {
    }
|   expression_or_null_list ',' expression {
    }
  ;

system_task_enable : 
    SYSTEM_ID ';' {
    }
|   SYSTEM_ID '(' expression_or_null_list ')' ';' {
    }
  ;

task_enable : 
    hierarchical_task_identifier ';' {
    }
|   hierarchical_task_identifier '(' expression_list ')' ';' {
    }
  ;

/*
A.7 Specify section
A.7.1 Specify block declaration
*/
specify_item_list :
    {
    }
|   specify_item {
    }
|   specify_item_list specify_item {
    }
  ;

specify_block : 
    KW_SPECIFY specify_item_list KW_ENDSPECIFY {
    }
  ;

specify_item :
    specparam_declaration {
    }
|   pulsestyle_declaration {
    }
|   showcancelled_declaration {
    }
|   path_declaration {
    }
|   system_timing_check {
    }
  ;

pulsestyle_declaration :
    KW_PULSESTYLE_ONEVENT list_of_path_outputs ';' {
    }
|   KW_PULSESTYLE_ONDETECT list_of_path_outputs ';' {
    }
  ;

showcancelled_declaration :
    KW_SHOWCANCELLED list_of_path_outputs ';' {
    }
|   KW_NOSHOWCANCELLED list_of_path_outputs ';' {
    }
  ;

/*
A.7.2 Specify path declarations
*/
path_declaration :
    simple_path_declaration ';' {
    }
|   edge_sensitive_path_declaration ';' {
    }
|   state_dependent_path_declaration ';' {
    }
  ;

simple_path_declaration : 
    parallel_path_description '=' path_delay_value {
    }
|   full_path_description '=' path_delay_value {
    }
  ;

polarity_operator_option:
    {
    }
|   polarity_operator {
    }
  ;

parallel_path_description :
    '(' specify_input_terminal_descriptor polarity_operator_option '=' '>' specify_output_terminal_descriptor ')' {
    }
  ;

full_path_description :
    '(' list_of_path_inputs polarity_operator_option '*' '>' list_of_path_outputs ')' {
    }
  ;

list_of_path_inputs :
    specify_input_terminal_descriptor {
    } 
|   list_of_path_inputs ',' specify_input_terminal_descriptor {
    }
  ;

list_of_path_outputs :
    specify_output_terminal_descriptor {
    }
|   list_of_path_outputs ',' specify_output_terminal_descriptor {
    }
  ;

/*
A.7.3 Specify block terminals
*/
specify_input_terminal_descriptor :
    input_identifier {
    }
|   input_identifier '[' constant_range_expression ']' {
    }
  ;

specify_output_terminal_descriptor :
    output_identifier {
    }
|   output_identifier '[' constant_range_expression ']' {
    }
  ;

input_identifier : 
    input_port_identifier  {
    }
|   inout_port_identifier {
    }
  ;

output_identifier : 
    output_port_identifier  {
    }
|   inout_port_identifier {
    }
  ;

/*
A.7.4 Specify path delays
*/
path_delay_value :
    list_of_path_delay_expressions {
    }
|   '(' list_of_path_delay_expressions ')' {
    }
  ;

list_of_path_delay_expressions :
    t_path_delay_expression {
    }
|   trise_path_delay_expression ',' tfall_path_delay_expression {
    }
|   trise_path_delay_expression ',' tfall_path_delay_expression ',' tz_path_delay_expression {
    }
|   t01_path_delay_expression ',' t10_path_delay_expression ',' t0z_path_delay_expression ','
    tz1_path_delay_expression ',' t1z_path_delay_expression ',' tz0_path_delay_expression {
    }
|   t01_path_delay_expression ',' t10_path_delay_expression ',' t0z_path_delay_expression ','
    tz1_path_delay_expression ',' t1z_path_delay_expression ',' tz0_path_delay_expression ','
    t0x_path_delay_expression ',' tx1_path_delay_expression ',' t1x_path_delay_expression ','
    tx0_path_delay_expression ',' txz_path_delay_expression ',' tzx_path_delay_expression {
    }
  ;

t_path_delay_expression : 
    path_delay_expression {
    }
  ;

trise_path_delay_expression : 
	path_delay_expression {
	}
  ;

tfall_path_delay_expression : 
	path_delay_expression {
	}
  ;

tz_path_delay_expression : 
	path_delay_expression {
	}
  ;

t01_path_delay_expression : 
	path_delay_expression {
	}
  ;

t10_path_delay_expression : 
	path_delay_expression {
	}
  ;

t0z_path_delay_expression : 
	path_delay_expression {
	}
  ;

tz1_path_delay_expression : 
	path_delay_expression {
	}
  ;

t1z_path_delay_expression : 
	path_delay_expression {
	}
  ;

tz0_path_delay_expression : 
	path_delay_expression {
	}
  ;
t0x_path_delay_expression : 
	path_delay_expression {
	}
  ;

tx1_path_delay_expression : 
	path_delay_expression {
	}
  ;

t1x_path_delay_expression : 
	path_delay_expression {
	}
  ;
tx0_path_delay_expression : 
	path_delay_expression {
	}
  ;

txz_path_delay_expression : 
	path_delay_expression {
	}
  ;

tzx_path_delay_expression : 
	path_delay_expression {
	}
  ;

path_delay_expression : 
    constant_mintypmax_expression {
    }
  ;

edge_sensitive_path_declaration :
    parallel_edge_sensitive_path_description '=' path_delay_value {
    }
|   full_edge_sensitive_path_description '=' path_delay_value {
    }
  ;

edge_identifier_option :
    {
    }
|   edge_identifier {
    }
  ;

polarity_operator_option :
    {
    }
|   polarity_operator {
    }
  ;
parallel_edge_sensitive_path_description :
    '(' edge_identifier_option specify_input_terminal_descriptor '=' '>' 
    '(' specify_output_terminal_descriptor polarity_operator_option ':' data_source_expression ')' ')' {
    }
  ;

full_edge_sensitive_path_description :
    '(' edge_identifier_option list_of_path_inputs '*' '>'
    '(' list_of_path_outputs polarity_operator_option ':' data_source_expression ')' ')' {
    }
  ;

data_source_expression : 
    expression {
    }
  ;

edge_identifier : 
    KW_POSEDGE {
    }
|   KW_NEGEDGE {
    }
  ;

state_dependent_path_declaration :
    KW_IF '(' module_path_expression ')' simple_path_declaration {
    }
|   KW_IF '(' module_path_expression ')' edge_sensitive_path_declaration {
    }
|   KW_IFNONE simple_path_declaration {
    }
  ;

polarity_operator : 
    '+'  {
    }
|   '-' {
    }
  ;

/*
A.7.5 System timing checks
A.7.5.1 System timing check commands
*/

system_timing_check :
    setup_timing_check {
    }
|   hold_timing_check{
    }
|   setuphold_timing_check {
    }
|   recovery_timing_check {
    }
|   removal_timing_check {
    }
|   recrem_timing_check {
    }
|   skew_timing_check {
    }
|   timeskew_timing_check {
    }
|   fullskew_timing_check {
    }
|   period_timing_check {
    }
|   width_timing_check {
    }
|   nochange_timing_check {
    }
  ;

notifier_or_null :
    {
    }
|   ',' {
    }
|   ',' notifier {
    }
  ;

setup_timing_check :
    KW_SYS_SETUP '(' data_event ',' reference_event ',' timing_check_limit notifier_or_null ')' ';' {
    }
  ;

hold_timing_check :
    KW_SYS_HOLD '(' reference_event ',' data_event ',' timing_check_limit notifier_or_null ')' ';' {
    }
  ;

notifier_option :
   {
    }
|   notifier {
    }
  ;

stamptime_condition_option :
    {
    }
|   stamptime_condition {
    }
  ;

checktime_condition_option :
    {
    }
|   checktime_condition {
    }
  ;

delayed_reference_option :
    {
    }
|   delayed_reference {
    }
  ;

delayed_data_option :
    {
    }
|   delayed_data {
    }
  ;

setuphold_timing_check :
    KW_SYS_SETUPHOLD '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ')' ';' {
    }
|   KW_SYS_SETUPHOLD '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option 
    ')' ';' {
    }
|   KW_SYS_SETUPHOLD '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option 
    ',' stamptime_condition_option 
    ')' ';' {
    }
|   KW_SYS_SETUPHOLD '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option 
    ',' stamptime_condition_option 
    ',' checktime_condition_option
     ')' ';' {
    }
|   KW_SYS_SETUPHOLD '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option 
    ',' stamptime_condition_option 
    ',' checktime_condition_option
    ',' delayed_reference_option 
    ')' ';' {
    }
|   KW_SYS_SETUPHOLD '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option 
    ',' stamptime_condition_option 
    ',' checktime_condition_option
    ',' delayed_reference_option 
    ',' delayed_data_option
    ')' ';' {
    }
  ;

recovery_timing_check :
    KW_SYS_RECOVERY '(' reference_event ',' data_event ',' timing_check_limit notifier_or_null ')' ';' {
    }
  ;

removal_timing_check :
    KW_SYS_REMOVAL '(' reference_event ',' data_event ',' timing_check_limit notifier_or_null ')' ';' {
    }
  ;

recrem_timing_check :
    KW_SYS_RECREM '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ')' ';' {
    }
|   KW_SYS_RECREM '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option
    ')' ';' {
    }
|   KW_SYS_RECREM '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option 
    ',' stamptime_condition_option
    ')' ';' {
    }
|   KW_SYS_RECREM '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option 
    ',' stamptime_condition_option 
    ',' checktime_condition_option
    ')' ';' {
    }
|   KW_SYS_RECREM '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option 
    ',' stamptime_condition_option 
    ',' checktime_condition_option
    ',' delayed_reference_option
    ')' ';' {
    }
|   KW_SYS_RECREM '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option 
    ',' stamptime_condition_option 
    ',' checktime_condition_option
    ',' delayed_reference_option  
    ',' delayed_data_option
    ')' ';' {
    }
  ;

skew_timing_check :
    KW_SYS_SKEW '(' reference_event ',' data_event ',' timing_check_limit notifier_or_null ')' ';' {
    }
  ;

timeskew_timing_check :
    KW_SYS_TIMESKEW '(' reference_event ',' data_event ',' timing_check_limit
    ')' ';' {
    }
|   KW_SYS_TIMESKEW '(' reference_event ',' data_event ',' timing_check_limit
    ',' notifier_option 
    ')' ';' {
    }
|   KW_SYS_TIMESKEW '(' reference_event ',' data_event ',' timing_check_limit
    ',' notifier_option 
    ',' event_based_flag_option
    ')' ';' {
    }
|   KW_SYS_TIMESKEW '(' reference_event ',' data_event ',' timing_check_limit
    ',' notifier_option 
    ',' event_based_flag_option
    ',' remain_active_flag_option
    ')' ';' {
    }
  ;

event_based_flag_option :
    {
    }
|   event_based_flag {
    }
  ;

remain_active_flag_option :
    {
    }
|   remain_active_flag {
    }
  ;

threshold_option :
    {
    }
|   threshold {
    }
  ;

fullskew_timing_check :
    KW_SYS_FULLSKEW '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ')' ';' {
    }
|   KW_SYS_FULLSKEW '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option
    ')' ';' {
    }

|   KW_SYS_FULLSKEW '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option
    ',' event_based_flag_option
    ')' ';' {
    }
|   KW_SYS_FULLSKEW '(' reference_event ',' data_event ',' timing_check_limit ',' timing_check_limit
    ',' notifier_option
    ',' event_based_flag_option
    ',' remain_active_flag_option 
    ')' ';' {
    }
  ;

period_timing_check :
    KW_SYS_PERIOD '(' controlled_reference_event ',' timing_check_limit notifier_or_null ')' ';' {
    }
  ;


width_timing_check :
    KW_SYS_WIDTH '(' controlled_reference_event ',' timing_check_limit
    ')' ';' {
    }
|   KW_SYS_WIDTH '(' controlled_reference_event ',' timing_check_limit
    ',' threshold_option 
    ')' ';' {
    }
|   KW_SYS_WIDTH '(' controlled_reference_event ',' timing_check_limit
    ',' threshold_option 
    ',' notifier_option 
    ')' ';' {
    }
  ;

nochange_timing_check :
    KW_SYS_NOCHANGE '(' reference_event ',' data_event ',' start_edge_offset ','
    end_edge_offset notifier_or_null ')' ';' {
    }
  ;

/*
A.7.5.2 System timing check command arguments
*/

checktime_condition : 
    mintypmax_expression {
    }
  ;

controlled_reference_event : 
    controlled_timing_check_event {
    }
  ;

data_event : 
    timing_check_event {
    }
  ;

delayed_data :
    terminal_identifier {
    }
|   terminal_identifier '[' constant_mintypmax_expression ']' {
    }
  ;

delayed_reference :
    terminal_identifier {
    }
|   terminal_identifier '[' constant_mintypmax_expression ']' {
    }
  ;

end_edge_offset :
    mintypmax_expression {
    }
 ;

event_based_flag : 
    constant_expression {
    }
  ;

notifier : 
    variable_identifier {
    }
  ;

reference_event : 
    timing_check_event {
    }
  ;

remain_active_flag : 
    constant_expression {
    }
  ;

stamptime_condition : 
    mintypmax_expression {
    }
  ;

start_edge_offset : 
    mintypmax_expression {
    }
  ;

threshold : 
    constant_expression {
    }
  ;

timing_check_limit : 
    expression {
    }
  ;



/*
A.7.5.3 System timing check event definitions
*/

timing_check_event_control_option :
    {
    }
|   timing_check_event_control {
    }
  ;

timing_check_event :
    timing_check_event_control_option specify_terminal_descriptor {
    }
|   timing_check_event_control_option specify_terminal_descriptor L_AND '&' timing_check_condition {
    }
  ;

controlled_timing_check_event :
    timing_check_event_control specify_terminal_descriptor {
    }
|   timing_check_event_control specify_terminal_descriptor L_AND '&' timing_check_condition {
    }
  ;

timing_check_event_control :
    KW_POSEDGE {
    }
|   KW_NEGEDGE {
    }
|   edge_control_specifier {
    }
  ;

specify_terminal_descriptor :
    specify_input_terminal_descriptor {
    }
|   specify_output_terminal_descriptor {
    }
  ;

edge_descriptor_list:
    {
    }
| edge_descriptor {
    }
| edge_descriptor_list ',' edge_descriptor {
    }
  ;

edge_control_specifier : 
    KW_EDGE edge_descriptor_list {
    }
  ;

edge_descriptor :
    number {
    }
  ;

/*
fixed me
edge_descriptor :
    01 {
    }
|   10 {
    }
|   z_or_x zero_or_one {
    }
|   zero_or_one z_or_x {
    }
  ;

zero_or_one : 0 | 1
z_or_x ::= x | X | z | Z
*/

timing_check_condition :
    scalar_timing_check_condition {
    }
|   '(' scalar_timing_check_condition ')' {
    }
  ;

scalar_timing_check_condition :
    expression {
    }
|   '~' expression {
    }
|   expression L_EQ scalar_constant {
    }
|   expression C_EQ scalar_constant {
    }
|   expression L_NEQ scalar_constant {
    }
|   expression C_NEQ scalar_constant {
    }
  ;

scalar_constant :
    number {
    }
  ;
/*
fixedme
1'b0 | 1'b1 | 1'B0 | 1'B1 | 'b0 | 'b1 | 'B0 | 'B1 | 1 | 0
*/

/*
A.8 Expressions
A.8.1 Concatenations
*/
concatenation : 
    '{' expression_list '}' {
    }
  ;

constant_expression_list :
    constant_expression {
    }
|   constant_expression_list ',' constant_expression {
    }
  ;

constant_concatenation : 
    '{' constant_expression_list '}' {
    }
  ;

constant_multiple_concatenation : 
    '{' constant_expression constant_concatenation '}' {
    }
  ;

module_path_expression_list :
    module_path_expression {
    }
|   module_path_expression_list ',' module_path_expression {
    }
  ;


module_path_concatenation : 
    '{' module_path_expression_list '}' {
    }
  ;

module_path_multiple_concatenation : 
    '{' constant_expression module_path_concatenation '}' {
    }
  ;

multiple_concatenation : 
    '{' constant_expression concatenation '}' {
    }
  ;

/*
A.8.2 Function calls
*/
constant_function_call : 
    function_identifier attribute_instance_list
    '(' constant_expression_list ')' {
    }
  ;

system_function_identifier :
    SYSTEM_ID {
    }
  ;

constant_system_function_call : 
    system_function_identifier
    '(' constant_expression_list ')' {
    }
  ;

function_call : 
    hierarchical_function_identifier attribute_instance_list
    '(' expression_list ')' {
    }
  ;

system_function_call : 
    system_function_identifier {
    }
|   system_function_identifier
    '(' expression_list ')' {
    }
  ;

/*
A.8.3 Expressions
*/
base_expression : 
    expression {
    }
  ;

conditional_expression : 
    expression '?' attribute_instance_list expression ':' expression {
    }
  ;

constant_base_expression : 
    constant_expression {
    }
  ;

constant_expression :
    constant_primary {
    }
|   unary_operator attribute_instance_list constant_primary {
    }
|   constant_expression binary_operator attribute_instance_list constant_expression {
    }
|   constant_expression '?' attribute_instance_list constant_expression ':' constant_expression {
    }
  ;

constant_mintypmax_expression :
    constant_expression {
    }
|   constant_expression ':' constant_expression ':' constant_expression {
    }
  ;

constant_range_expression :
    constant_expression {
    }
|   msb_constant_expression ':' lsb_constant_expression {
    }
|   constant_base_expression '+' ':' width_constant_expression {
    }
|   constant_base_expression '-' ':' width_constant_expression {
    }
  ;

dimension_constant_expression :
    constant_expression {
    }
  ;

expression :
    primary {
    }
|   unary_operator attribute_instance_list primary {
    }
|   expression binary_operator attribute_instance_list expression {
    }
|   conditional_expression {
    }
  ;

/*
expression1 ::= expression
expression2 ::= expression
expression3 ::= expression
*/

lsb_constant_expression : 
    constant_expression {
    }
  ;

mintypmax_expression :
    expression {
    }
|   expression ':' expression ':' expression {
    }
  ;

module_path_conditional_expression : 
    module_path_expression '?' attribute_instance_list
    module_path_expression ':' module_path_expression {
    }
  ;

module_path_expression :
    module_path_primary {
    }
|   unary_module_path_operator attribute_instance_list module_path_primary {
    }
|   module_path_expression binary_module_path_operator 
    attribute_instance_list module_path_expression {
    }
|   module_path_conditional_expression {
    }
  ;

module_path_mintypmax_expression :
    module_path_expression {
    }
|   module_path_expression ':' module_path_expression ':' module_path_expression {
    }
  ;

msb_constant_expression : 
    constant_expression {
    }
  ;

range_expression :
    expression {
    }
|   msb_constant_expression ':' lsb_constant_expression {
    }
|   base_expression '+' ':' width_constant_expression {
    }
|   base_expression '-' ':' width_constant_expression {
    }
  ;

width_constant_expression : 
    constant_expression {
    }
  ;

/*
A.8.4 Primaries
*/
constant_primary :
    number {
    }
|   parameter_identifier {
    }
|   parameter_identifier '[' constant_range_expression ']' {
    }
|   specparam_identifier  {
    }
|   specparam_identifier '[' constant_range_expression ']' {
    }
|   constant_concatenation {
    }
|   constant_multiple_concatenation {
    }
|   constant_function_call {
    }
|   constant_system_function_call {
    }
|   '(' constant_mintypmax_expression ')' {
    }
|   string {
    }
  ;

module_path_primary :
    number {
    }
|   identifier {
    }
|   module_path_concatenation {
    }
|   module_path_multiple_concatenation {
    }
|   function_call {
    }
|   system_function_call {
    }
|   '(' module_path_mintypmax_expression ')' {
    }
  ;

array_element_select :
    {
    }
|   '[' expression ']' {
    }
|   array_element_select '[' expression ']' {
    }
  ;

range_expression_option :
    {
    }
| range_expression {
    }
  ;

primary :
    number {
    }
|   hierarchical_identifier array_element_select range_expression_option {
    }
|   concatenation {
    }
|   multiple_concatenation {
    }
|   function_call {
    }
|   system_function_call {
    }
|   '(' mintypmax_expression ')' {
    }
|   string {
    }
  ;

/*
A.8.5 Expression left-side values
*/
const_array_element_select :
    {
    }
|   '[' constant_expression ']' {
    }
|   const_array_element_select '[' constant_expression ']' {
    }
  ;

constant_range_expression_option :
    {
    }
| range_expression {
    }
  ;

net_lvalue_list :
    net_lvalue {
    }
|   net_lvalue_list ',' net_lvalue {
    }
  ;

net_lvalue :
    hierarchical_net_identifier const_array_element_select constant_range_expression_option {
    }
|   '{' net_lvalue_list '}' {
    }
  ;

variable_lvalue_list :
    variable_lvalue {
    }
|   variable_lvalue_list ',' variable_lvalue {
    }
  ;

variable_lvalue :
    hierarchical_variable_identifier array_element_select range_expression_option {
    }
|   '{' variable_lvalue_list '}' {
    }
  ;

/*
A.8.6 Operators
*/

unary_operator :
    '+'  {
    }
|   '-'  {
    }
|   '!'  {
    }
|   '~'  {
    }
|   '&'  {
    }
|   B_NAND {
    } 
|   '|' {
    } 
|   B_NOR {
    } 
|   '^' {
    } 
|   B_EQU  {
    }
  ;

binary_operator :
    '+' {
    }
|   '-' {
    }
|   '*'  {
    }
|   '/' {
    } 
|   '%' {
    } 
|   L_EQ {
    }
|   L_NEQ {
    }
|   C_EQ {
    } 
|   C_NEQ {
    } 
|   L_AND  {
    }
|   L_OR  {
    }
|   POW {
    }
|   '<' {
    } 
|   LTE  {
    }
|   '>' {
    } 
|   GTE  {
    }
|   '&' {
    } 
|   '|' {
    } 
|   '^' {
    } 
|   B_EQU {
    }
|   LSR  {
    }
|   LSL  {
    }
|   ASR {
    } 
|   ASL {
    }
  ;

unary_module_path_operator :
    '!'  {
    }
|   '~'  {
    }
|   '&'  {
    }
|   B_NAND  {
    }
|   '|'  {
    }
|   B_NOR  {
    }
|   '^'  {
    }
|   B_EQU  {
    }
  ;

binary_module_path_operator :
    L_EQ  {
    }
|   L_NEQ {
    } 
|   L_AND {
    } 
|   L_OR {
    } 
|   '&' {
    }
|   '|'  {
    }
|   '^'  {
    }
|   B_EQU  {
    }
 ;

/*
A.8.7 Numbers
*/
/*
number ::=
decimal_number
| octal_number
| binary_number
| hex_number
| real_number
real_number ::=
unsigned_number . unsigned_number
| unsigned_number [ . unsigned_number ] exp [ sign ] unsigned_number
exp ::= e | E
decimal_number ::=
unsigned_number
| [ size ] decimal_base unsigned_number
| [ size ] decimal_base x_digit { _ }
| [ size ] decimal_base z_digit { _ }
binary_number ::= [ size ] binary_base binary_value
octal_number ::= [ size ] octal_base octal_value
hex_number ::= [ size ] hex_base hex_value
sign ::= + | -
size ::= non_zero_unsigned_number
non_zero_unsigned_number2 ::= non_zero_decimal_digit { _ | decimal_digit}
unsigned_number2 ::= decimal_digit { _ | decimal_digit }
binary_value2 ::= binary_digit { _ | binary_digit }
octal_value2 ::= octal_digit { _ | octal_digit }
hex_value2 ::= hex_digit { _ | hex_digit }
decimal_base2 ::= '[s|S]d | '[s|S]D
binary_base2 ::= '[s|S]b | '[s|S]B
octal_base2 ::= '[s|S]o | '[s|S]O
hex_base2 ::= '[s|S]h | '[s|S]H
non_zero_decimal_digit ::= 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
decimal_digit ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
binary_digit ::= x_digit | z_digit | 0 | 1
octal_digit ::= x_digit | z_digit | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7
hex_digit ::=
x_digit | z_digit | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
| a | b | c | d | e | f | A | B | C | D | E | F
x_digit ::= x | X
z_digit ::= z | Z | ?
*/

unsigned_number :
  UNSIGNED_NUMBER {
  }
;

number :
    NUM_REAL{
    }
|   BIN_BASE BIN_VALUE {
    }
|   HEX_BASE HEX_VALUE {
    }
|   OCT_BASE OCT_VALUE {
    }
|   DEC_BASE UNSIGNED_NUMBER{
    }
|   UNSIGNED_NUMBER BIN_BASE BIN_VALUE {
    }
|   UNSIGNED_NUMBER HEX_BASE HEX_VALUE {
    }
|   UNSIGNED_NUMBER OCT_BASE OCT_VALUE {
    }
|   UNSIGNED_NUMBER DEC_BASE UNSIGNED_NUMBER{
    }
|   unsigned_number {
    }
;


/*
A.8.8 Strings
*/
string : 
    STRING {
    }
  ;

/* string ::= " { Any_ASCII_Characters_except_new_line } " */
/*
A.9 General
A.9.1 Attributes
*/
attribute_instance_list :
    {
    }
|   attribute_instance_list attribute_instance {
    }
|   attribute_instance {
    }
 ;

attribute_instance : 
    ATTRIBUTE_START attribute_instance_spec_list ATTRIBUTE_END {
    }
 ;
attribute_instance_spec_list : 
    attribute_instance_spec_list ',' attr_spec {
    }
|   attr_spec {
    }
 ;

attr_spec :
    attr_name {
    }
|   attr_name  '=' constant_expression {
    }
  ;

attr_name : 
    identifier {
    }
 ;
/*
A.9.2 Comments
*/

/*
comment ::=
one_line_comment
| block_comment
one_line_comment ::= // comment_text \n
block_comment ::= / * comment_text * /
comment_text ::= { Any_ASCII_character }
*/

/*
A.9.3 Identifiers
*/

block_identifier : 
    identifier {
    }
 ;

cell_identifier : 
    identifier {
    }
  ;

config_identifier :
    identifier {
    }
  ;

event_identifier : 
    identifier  {
    }
 ;

function_identifier :  
    identifier {
    }
 ;

gate_instance_identifier : 
    identifier  {
    }
 ;

generate_block_identifier : 
    identifier {
    }
 ;

genvar_identifier : 
    identifier {
    }
 ;

hierarchical_block_identifier : 
    hierarchical_identifier {
    }
  ;

hierarchical_event_identifier : 
    hierarchical_identifier {
    }
  ;

hierarchical_function_identifier : 
    hierarchical_identifier {
    }
  ;

hierachical_header:
    {
    }
|   identifier '.' {
    }
|   identifier '[' constant_expression ']' '.' {
    }
|   hierachical_header identifier '.' {
    }
|   hierachical_header identifier '[' constant_expression ']' '.' {
    }
 ;
    
hierarchical_identifier : 
  hierachical_header identifier {
  }
 ;

hierarchical_net_identifier : 
    hierarchical_identifier {
    }
 ;

hierarchical_parameter_identifier : 
    hierarchical_identifier {
    }
  ;

hierarchical_variable_identifier : 
    hierarchical_identifier {
    }
  ;

hierarchical_task_identifier : 
    hierarchical_identifier {
    }
  ;

identifier :
    SIMPLE_ID {
    }
|   ESCAPED_ID {
    }
  ;

inout_port_identifier : 
    identifier {
    }
  ;

input_port_identifier : 
    identifier {
    }
  ;

instance_identifier : 
    identifier {
    }
  ;

library_identifier : 
    identifier {
    }
  ;

module_identifier : 
    identifier {
    }
  ;

module_instance_identifier : 
    identifier {
    }
 ;
net_identifier : identifier {
    }
  ;

output_port_identifier : 
    identifier {
    }
  ;

parameter_identifier : 
    identifier {
    }
  ;

port_identifier : 
    identifier {
    }
  ;

real_identifier : 
    identifier {
    }
  ;

specparam_identifier : 
    identifier {
    }
  ;

task_identifier : 
    identifier {
    }
  ;

terminal_identifier : 
    identifier {
    }
  ;

/* handle by preprocess
text_macro_identifier : 
    identifier {
    }
  ;
*/

topmodule_identifier : 
    identifier {
    }
  ;

udp_identifier : 
    identifier {
    }
  ;

udp_instance_identifier : 
    identifier {
    }
  ;
variable_identifier : 
    identifier {
    }
  ;

/*
A.9.4 White space
*/
/*
white_space : 
    space  {
    }
|   tab {
    }
|   newline {
    }
|   eof {
    }
  ;
*/
%%