%term FOR IN WHILE IF NOT TWIDDLE BANG SUBSHELL SWITCH FN%term WORD REDIR DUP PIPE SUB%term BREAK%term SIMPLE ARGLIST WORDS BRACE PAREN PCMD PIPEFD /* not used in syntax *//* operator priorities -- lowest first */%left IF WHILE FOR SWITCH ')' NOT%left ANDAND OROR%left BANG SUBSHELL%left PIPE%left '^'%right '$' COUNT '"'%left SUB%{#include "rc.h"#include "fns.h" inthcompile(tree *t){	int i; 	if(i = compile(t))		whistory(t);	return !i;} %}%union{	struct tree *tree;};%type<tree> line paren brace body cmdsa cmdsan assign epilog redir%type<tree> cmd simple first word nkword comword keyword nkwords words wordsnl%type<tree> NOT FOR IN WHILE IF TWIDDLE BANG SUBSHELL SWITCH FN BREAK%type<tree> WORD REDIR DUP PIPE%%rc:				{ return 1;}|	line '\n'			{ return hcompile($1); }line:	cmd|	cmdsa line		{$$=tree2(';', $1, $2);}body:	cmd|	cmdsan body		{$$=tree2(';', $1, $2);}cmdsa:	cmd ';'|	cmd '&'			{$$=tree1('&', $1);}cmdsan:	cmdsa|	cmd '\n'brace:	'{' body '}'		{$$=tree1(BRACE, $2);}paren:	'(' body ')'		{$$=tree1(PCMD, $2);}assign:	first '=' word		{$$=tree2('=', $1, $3);}epilog:				{$$=0;}|	redir epilog		{$$=mung2($1, $1->child[0], $2);}redir:	REDIR word		{$$=mung1($1, $1->rtype==HERE?heredoc($2):$2);}|	DUPcmd:				{$$=0;}|	brace epilog		{$$=epimung($1, $2);}|	IF paren {skipnl();} cmd				{$$=mung2($1, $2, $4);}|	IF NOT {skipnl();} cmd	{$$=mung1($2, $4);}|	FOR '(' word IN words ')' {skipnl();} cmd	/*	 * if ``words'' is nil, we need a tree element to distinguish between 	 * for(i in ) and for(i), the former being a loop over the empty set	 * and the latter being the implicit argument loop.  so if $5 is nil	 * (the empty set), we represent it as "()".  don't parenthesize non-nil	 * functions, to avoid growing parentheses every time we reread the	 * definition.	 */				{$$=mung3($1, $3, $5 ? $5 : tree1(PAREN, $5), $8);}|	FOR '(' word ')' {skipnl();} cmd				{$$=mung3($1, $3, (struct tree *)0, $6);}|	WHILE paren {skipnl();} cmd				{$$=mung2($1, $2, $4);}|	BREAK			{$$=tree1(BREAK, 0);}|	SWITCH word {skipnl();} brace				{$$=tree2(SWITCH, $2, $4);}|	simple			{$$=simplemung($1);}|	TWIDDLE word words	{$$=mung2($1, $2, $3);}|	cmd ANDAND cmd		{$$=tree2(ANDAND, $1, $3);}|	cmd OROR cmd		{$$=tree2(OROR, $1, $3);}|	cmd PIPE cmd		{$$=mung2($2, $1, $3);}|	redir cmd  %prec BANG	{$$=mung2($1, $1->child[0], $2);}|	assign cmd %prec BANG	{$$=mung3($1, $1->child[0], $1->child[1], $2);}|	BANG cmd		{$$=mung1($1, $2);}|	SUBSHELL cmd		{$$=mung1($1, $2);}|	FN nkwords brace		{$$=tree2(FN, $2, $3);}|	FN nkwords		{$$=tree1(FN, $2);}simple:	first|	simple word		{$$=tree2(ARGLIST, $1, $2);}|	simple redir		{$$=tree2(ARGLIST, $1, $2);}first:	comword	|	first '^' word		{$$=tree2('^', $1, $3);}word:	keyword			{lastword=1; $1->type=WORD;}|	comword|	word '^' word		{$$=tree2('^', $1, $3);}nkword:	comword|	word '^' word		{$$=tree2('^', $1, $3);}comword: '$' word		{$$=tree1('$', $2);}|	'$' word SUB words ')'	{$$=tree2(SUB, $2, $4);}|	'"' word		{$$=tree1('"', $2);}|	COUNT word		{$$=tree1(COUNT, $2);}|	WORD|	'`' brace		{$$=tree2('`', nil, $2);}|	'`' word brace		{$$=tree2('`', $2, $3);}|	'(' wordsnl nl ')'		{$$=tree1(PAREN, $2);}|	REDIR brace		{$$=mung1($1, $2); $$->type=PIPEFD;}keyword: FOR|IN|WHILE|IF|NOT|TWIDDLE|BANG|SUBSHELL|SWITCH|FN|BREAKwordsnl:				{$$=(struct tree*)0;}|	wordsnl nl word 		{$$=tree2(WORDS, $1, $3);}nl:	'\n' nl|	words:				{$$=(struct tree*)0;}|	words word		{$$=tree2(WORDS, $1, $2);}nkwords:				{$$=(struct tree*)0;}|	nkwords nkword		{$$=tree2(WORDS, $1, $2);}