%token IF THEN ELSE ELIF FI CASE ESAC FOR SELECT WHILE UNTIL DO DONE FUNCTION
%token COND_START COND_END COND_ERROR
%token IN BANG TIME TIMEOPT
%token <word> WORD ASSIGNMENT_WORD
%token <number> NUMBER
%token <word_list> ARITH_CMD ARITH_FOR_EXPRS
%token <command> COND_CMD
%token AND_AND OR_OR GREATER_GREATER LESS_LESS LESS_AND
%token GREATER_AND SEMI_SEMI LESS_LESS_MINUS AND_GREATER LESS_GREATER
%token GREATER_BAR
%token yacc_EOF
	/*
	%type <command> inputunit command pipeline pipeline_command
	%type <command> list list0 list1 compound_list simple_list simple_list1
	%type <command> simple_command shell_command
	%type <command> for_command select_command case_command group_command
	%type <command> arith_command
	%type <command> cond_command
	%type <command> arith_for_command
	%type <command> function_def function_body if_command elif_clause subshell
	%type <redirect> redirection redirection_list
	%type <element> simple_command_element
	%type <word_list> word_list pattern
	%type <pattern> pattern_list case_clause_sequence case_clause
	%type <number> timespec
	*/
%start inputunit
	/*
	%left '&' ';' '\n' yacc_EOF
	%left AND_AND OR_OR
	%right '|'
	*/
%%
inputunit:	simple_list '\n'
			
	|	'\n'
			
	|	error '\n'
			
	|	yacc_EOF
			
	;
word_list:	WORD
			
	|	word_list WORD
			
	;
redirection:	'>' WORD
			
	|	'<' WORD
			
	|	NUMBER '>' WORD
			
	|	NUMBER '<' WORD
			
	|	GREATER_GREATER WORD
			
	|	NUMBER GREATER_GREATER WORD
			
	|	LESS_LESS WORD
			
	|	NUMBER LESS_LESS WORD
			
	|	LESS_AND NUMBER
			
	|	NUMBER LESS_AND NUMBER
			
	|	GREATER_AND NUMBER
			
	|	NUMBER GREATER_AND NUMBER
			
	|	LESS_AND WORD
			
	|	NUMBER LESS_AND WORD
			
	|	GREATER_AND WORD
			
	|	NUMBER GREATER_AND WORD
			
	|	LESS_LESS_MINUS WORD
			
	|	NUMBER LESS_LESS_MINUS WORD
			
	|	GREATER_AND '-'
			
	|	NUMBER GREATER_AND '-'
			
	|	LESS_AND '-'
			
	|	NUMBER LESS_AND '-'
			
	|	AND_GREATER WORD
			
	|	NUMBER LESS_GREATER WORD
			
	|	LESS_GREATER WORD
			
	|	GREATER_BAR WORD
			
	|	NUMBER GREATER_BAR WORD
			
	;
simple_command_element: WORD
			
	|	ASSIGNMENT_WORD
			
	|	redirection
			
	;
redirection_list: redirection
			
	|	redirection_list redirection
			
	;
simple_command:	simple_command_element
			
	|	simple_command simple_command_element
			
	;
command:	simple_command
			
	|	shell_command
			
	|	shell_command redirection_list
			
	|	function_def
			
	;
shell_command:	for_command
			
	|	case_command
			
 	|	WHILE compound_list DO compound_list DONE
			
	|	UNTIL compound_list DO compound_list DONE
			
	|	select_command
			
	|	if_command
			
	|	subshell
			
	|	group_command
			
	|	arith_command
			
	|	cond_command
			
	|	arith_for_command
			
	;
for_command:	FOR WORD newline_list DO compound_list DONE
			
	|	FOR WORD newline_list '{' compound_list '}'
			
	|	FOR WORD ';' newline_list DO compound_list DONE
			
	|	FOR WORD ';' newline_list '{' compound_list '}'
			
	|	FOR WORD newline_list IN word_list list_terminator newline_list DO compound_list DONE
			
	|	FOR WORD newline_list IN word_list list_terminator newline_list '{' compound_list '}'
			
	;
arith_for_command:	FOR ARITH_FOR_EXPRS list_terminator newline_list DO compound_list DONE
				
	|		FOR ARITH_FOR_EXPRS list_terminator newline_list '{' compound_list '}'
				
	|		FOR ARITH_FOR_EXPRS DO compound_list DONE
				
	|		FOR ARITH_FOR_EXPRS '{' compound_list '}'
				
	;
select_command:	SELECT WORD newline_list DO list DONE
			
	|	SELECT WORD newline_list '{' list '}'
			
	|	SELECT WORD ';' newline_list DO list DONE
			
	|	SELECT WORD ';' newline_list '{' list '}'
			
	|	SELECT WORD newline_list IN word_list list_terminator newline_list DO list DONE
			
	|	SELECT WORD newline_list IN word_list list_terminator newline_list '{' list '}'
			
	;
case_command:	CASE WORD newline_list IN newline_list ESAC
			
	|	CASE WORD newline_list IN case_clause_sequence newline_list ESAC
			
	|	CASE WORD newline_list IN case_clause ESAC
			
	;
function_def:	WORD '(' ')' newline_list function_body
			
	|	FUNCTION WORD newline_list '(' ')' newline_list function_body
			
	|	FUNCTION WORD newline_list function_body
			
	;
function_body:	shell_command
			
	|	shell_command redirection_list
			
	;
subshell:	'(' compound_list ')'
			
	;
if_command:	IF compound_list THEN compound_list FI
			
	|	IF compound_list THEN compound_list ELSE compound_list FI
			
	|	IF compound_list THEN compound_list elif_clause FI
			
	;
group_command:	'{' compound_list '}'
			
	;
arith_command:	ARITH_CMD
			
	;
cond_command:	COND_START COND_CMD COND_END
			
	; 
elif_clause:	ELIF compound_list THEN compound_list
			
	|	ELIF compound_list THEN compound_list ELSE compound_list
			
	|	ELIF compound_list THEN compound_list elif_clause
			
	;
case_clause:	pattern_list
	|	case_clause_sequence pattern_list
			
	;
pattern_list:	newline_list pattern ')' compound_list
			
	|	newline_list pattern ')' newline_list
			
	|	newline_list '(' pattern ')' compound_list
			
	|	newline_list '(' pattern ')' newline_list
			
	;
case_clause_sequence:  pattern_list SEMI_SEMI
	|	case_clause_sequence pattern_list SEMI_SEMI
			
	;
pattern:	WORD
			
	|	pattern '|' WORD
			
	;
list:		newline_list list0
			
	;
compound_list:	list
	|	newline_list list1
			
	;
list0:  	list1 '\n' newline_list
	|	list1 '&' newline_list
			
	|	list1 ';' newline_list
	;
list1:		list1 '&' newline_list list2
			
	|	list1 ';' newline_list list2
			
	|	list1 '\n' newline_list list2
			
	|	list2
			
	;
list2:		list2 AND_AND newline_list pipeline_command
			
	|	list2 OR_OR newline_list pipeline_command
			
	|	pipeline_command
			
	;
list_terminator:'\n'
	|	';'
	|	yacc_EOF
	;
newline_list:
	|	newline_list '\n'
	;
simple_list:	simple_list1
			
	|	simple_list1 '&'
			
	|	simple_list1 ';'
			
	;
simple_list1:	simple_list1 '&' simple_list2
			
	|	simple_list1 ';' simple_list2
			
	|	simple_list2
			
	;
simple_list2:	simple_list2 AND_AND newline_list pipeline_command
			
	|	simple_list2 OR_OR newline_list pipeline_command
			
	|	pipeline_command
			
	;
pipeline_command: pipeline
			
	|	BANG pipeline
			
	|	timespec pipeline
			
	|	timespec BANG pipeline
			
	|	BANG timespec pipeline
			
	;
pipeline:
		command '|' newline_list pipeline
			
	|	command
			
	;
timespec:	TIME
			
	|	TIME TIMEOPT
			
	;