usr/src/cmd/awk/awk.g.y

%token  FIRSTTOKEN      /*must be first*/
%token  FINAL FATAL
%token  LT LE GT GE EQ NE
%token  MATCH NOTMATCH
%token  APPEND
%token  ADD MINUS MULT DIVIDE MOD UMINUS
%token  ASSIGN ADDEQ SUBEQ MULTEQ DIVEQ MODEQ
%token  JUMP
%token  XBEGIN XEND
%token  NL
%token  PRINT PRINTF SPRINTF SPLIT
%token  IF ELSE WHILE FOR IN NEXT EXIT BREAK CONTINUE
%token  PROGRAM PASTAT PASTAT2

%right  ASGNOP
%left   BOR
%left   AND
%left   NOT
%left   NUMBER VAR ARRAY FNCN SUBSTR LSUBSTR INDEX
%nonassoc RELOP MATCHOP
%left   OR
%left   STRING  DOT CCL NCCL CHAR
%left   '(' '^' '$'
%left   CAT
%left   '+' '-'
%left   '*' '/' '%'
%left   STAR PLUS QUEST
%left   POSTINCR PREINCR POSTDECR PREDECR INCR DECR
%left   FIELD INDIRECT
%token  LASTTOKEN       /* has to be last */

%{
#include "awk.def"
#ifndef DEBUG
#       define  PUTS(x)
#endif
%}
%%

program:
          begin pa_stats end    { if (errorflag==0) winner = stat3(PROGRAM, $1, $2, $3); }
        | error                 { yyclearin; yyerror("bailing out"); }
        ;

begin:
          XBEGIN '{' stat_list '}'      { PUTS("XBEGIN list"); $$ = $3; }
        | begin NL
        |       { PUTS("empty XBEGIN"); $$ = nullstat; }
        ;

end:
          XEND '{' stat_list '}'        { PUTS("XEND list"); $$ = $3; }
        | end NL
        |       { PUTS("empty END"); $$ = nullstat; }
        ;

compound_conditional:
          conditional BOR conditional   { PUTS("cond||cond"); $$ = op2(BOR, $1, $3); }
        | conditional AND conditional   { PUTS("cond&&cond"); $$ = op2(AND, $1, $3); }
        | NOT conditional               { PUTS("!cond"); $$ = op1(NOT, $2); }
        | '(' compound_conditional ')'  { $$ = $2; }
        ;

compound_pattern:
          pattern BOR pattern   { PUTS("pat||pat"); $$ = op2(BOR, $1, $3); }
        | pattern AND pattern   { PUTS("pat&&pat"); $$ = op2(AND, $1, $3); }
        | NOT pattern           { PUTS("!pat"); $$ = op1(NOT, $2); }
        | '(' compound_pattern ')'      { $$ = $2; }
        ;

conditional:
          expr  { PUTS("expr"); $$ = op2(NE, $1, valtonode(lookup("0", symtab), CCON)); }
        | rel_expr              { PUTS("relexpr"); }
        | lex_expr              { PUTS("lexexpr"); }
        | compound_conditional  { PUTS("compcond"); }
        ;

else:
          ELSE optNL    { PUTS("else"); }
        ;

field:
          FIELD         { PUTS("field"); $$ = valtonode($1, CFLD); }
        | INDIRECT term { PUTS("ind field"); $$ = op1(INDIRECT, $2); }
        ;

if:
          IF '(' conditional ')' optNL  { PUTS("if(cond)"); $$ = $3; }
        ;

lex_expr:
          expr MATCHOP regular_expr     { PUTS("expr~re"); $$ = op2($2, $1, makedfa($3)); }
        | '(' lex_expr ')'      { PUTS("(lex_expr)"); $$ = $2; }
        ;

var:
          NUMBER        {PUTS("number"); $$ = valtonode($1, CCON); }
        | STRING        { PUTS("string"); $$ = valtonode($1, CCON); }
        | VAR           { PUTS("var"); $$ = valtonode($1, CVAR); }
        | VAR '[' expr ']'      { PUTS("array[]"); $$ = op2(ARRAY, $1, $3); }
        | field
        ;
term:
          var
        | FNCN          { PUTS("func");
                        $$ = op2(FNCN, $1, valtonode(lookup("$record", symtab), CFLD));
                        }
        | FNCN '(' ')'  { PUTS("func()");
                        $$ = op2(FNCN, $1, valtonode(lookup("$record", symtab), CFLD));
                        }
        | FNCN '(' expr ')'     { PUTS("func(expr)"); $$ = op2(FNCN, $1, $3); }
        | SPRINTF print_list    { PUTS("sprintf"); $$ = op1($1, $2); }
        | SUBSTR '(' expr ',' expr ',' expr ')'
                        { PUTS("substr(e,e,e)"); $$ = op3(SUBSTR, $3, $5, $7); }
        | SUBSTR '(' expr ',' expr ')'
                        { PUTS("substr(e,e,e)"); $$ = op3(SUBSTR, $3, $5, nullstat); }
        | SPLIT '(' expr ',' VAR ',' expr ')'
                        { PUTS("split(e,e,e)"); $$ = op3(SPLIT, $3, $5, $7); }
        | SPLIT '(' expr ',' VAR ')'
                        { PUTS("split(e,e,e)"); $$ = op3(SPLIT, $3, $5, nullstat); }
        | INDEX '(' expr ',' expr ')'
                        { PUTS("index(e,e)"); $$ = op2(INDEX, $3, $5); }
        | '(' expr ')'                  {PUTS("(expr)");  $$ = $2; }
        | term '+' term                 { PUTS("t+t"); $$ = op2(ADD, $1, $3); }
        | term '-' term                 { PUTS("t-t"); $$ = op2(MINUS, $1, $3); }
        | term '*' term                 { PUTS("t*t"); $$ = op2(MULT, $1, $3); }
        | term '/' term                 { PUTS("t/t"); $$ = op2(DIVIDE, $1, $3); }
        | term '%' term                 { PUTS("t%t"); $$ = op2(MOD, $1, $3); }
        | '-' term %prec QUEST          { PUTS("-term"); $$ = op1(UMINUS, $2); }
        | '+' term %prec QUEST          { PUTS("+term"); $$ = $2; }
        | INCR var      { PUTS("++var"); $$ = op1(PREINCR, $2); }
        | DECR var      { PUTS("--var"); $$ = op1(PREDECR, $2); }
        | var INCR      { PUTS("var++"); $$= op1(POSTINCR, $1); }
        | var DECR      { PUTS("var--"); $$= op1(POSTDECR, $1); }
        ;

expr:
          term          { PUTS("term"); }
        | expr term     { PUTS("expr term"); $$ = op2(CAT, $1, $2); }
        | var ASGNOP expr       { PUTS("var=expr"); $$ = stat2($2, $1, $3); }
        ;

optNL:
          NL
        |
        ;

pa_stat:
          pattern       { PUTS("pattern"); $$ = stat2(PASTAT, $1, genprint()); }
        | pattern '{' stat_list '}'     { PUTS("pattern {...}"); $$ = stat2(PASTAT, $1, $3); }
        | pattern ',' pattern           { PUTS("srch,srch"); $$ = pa2stat($1, $3, genprint()); }
        | pattern ',' pattern '{' stat_list '}'
                                        { PUTS("srch, srch {...}"); $$ = pa2stat($1, $3, $5); }
        | '{' stat_list '}'     { PUTS("null pattern {...}"); $$ = stat2(PASTAT, nullstat, $2); }
        ;

pa_stats:
          pa_stats pa_stat st   { PUTS("pa_stats pa_stat"); $$ = linkum($1, $2); }
        |       { PUTS("null pa_stat"); $$ = nullstat; }
        | pa_stats pa_stat      {PUTS("pa_stats pa_stat"); $$ = linkum($1, $2); }
        ;

pattern:
          regular_expr  { PUTS("regex");
                $$ = op2(MATCH, valtonode(lookup("$record", symtab), CFLD), makedfa($1));
                }
        | rel_expr      { PUTS("relexpr"); }
        | lex_expr      { PUTS("lexexpr"); }
        | compound_pattern      { PUTS("comp pat"); }
        ;

print_list:
          expr  { PUTS("expr"); }
        | pe_list       { PUTS("pe_list"); }
        |               { PUTS("null print_list"); $$ = valtonode(lookup("$record", symtab), CFLD); }
        ;

pe_list:
          expr ',' expr {$$ = linkum($1, $3); }
        | pe_list ',' expr      {$$ = linkum($1, $3); }
        | '(' pe_list ')'               {$$ = $2; }
        ;

redir:
          RELOP
        | '|'
        ;

regular_expr:
          '/'   { startreg(); }
          r '/'
                { PUTS("/r/"); $$ = $3; }
        ;

r:
          CHAR          { PUTS("regex CHAR"); $$ = op2(CHAR, (node *) 0, $1); }
        | DOT           { PUTS("regex DOT"); $$ = op2(DOT, (node *) 0, (node *) 0); }
        | CCL           { PUTS("regex CCL"); $$ = op2(CCL, (node *) 0, cclenter($1)); }
        | NCCL          { PUTS("regex NCCL"); $$ = op2(NCCL, (node *) 0, cclenter($1)); }
        | '^'           { PUTS("regex ^"); $$ = op2(CHAR, (node *) 0, HAT); }
        | '$'           { PUTS("regex $"); $$ = op2(CHAR, (node *) 0 ,(node *) 0); }
        | r OR r        { PUTS("regex OR"); $$ = op2(OR, $1, $3); }
        | r r   %prec CAT
                        { PUTS("regex CAT"); $$ = op2(CAT, $1, $2); }
        | r STAR        { PUTS("regex STAR"); $$ = op2(STAR, $1, (node *) 0); }
        | r PLUS        { PUTS("regex PLUS"); $$ = op2(PLUS, $1, (node *) 0); }
        | r QUEST       { PUTS("regex QUEST"); $$ = op2(QUEST, $1, (node *) 0); }
        | '(' r ')'     { PUTS("(regex)"); $$ = $2; }
        ;

rel_expr:
          expr RELOP expr
                { PUTS("expr relop expr"); $$ = op2($2, $1, $3); }
        | '(' rel_expr ')'
                { PUTS("(relexpr)"); $$ = $2; }
        ;

st:
          NL
        | ';'
        ;

simple_stat:
          PRINT print_list redir expr
                { PUTS("print>stat"); $$ = stat3($1, $2, $3, $4); }
        | PRINT print_list
                { PUTS("print list"); $$ = stat3($1, $2, nullstat, nullstat); }
        | PRINTF print_list redir expr
                { PUTS("printf>stat"); $$ = stat3($1, $2, $3, $4); }
        | PRINTF print_list
                { PUTS("printf list"); $$ = stat3($1, $2, nullstat, nullstat); }
        | expr  { PUTS("expr"); $$ = exptostat($1); }
        |               { PUTS("null simple statement"); $$ = nullstat; }
        | error         { yyclearin; yyerror("illegal statement"); }
        ;

statement:
          simple_stat st        { PUTS("simple stat"); }
        | if statement          { PUTS("if stat"); $$ = stat3(IF, $1, $2, nullstat); }
        | if statement else statement
                { PUTS("if-else stat"); $$ = stat3(IF, $1, $2, $4); }
        | while statement       { PUTS("while stat"); $$ = stat2(WHILE, $1, $2); }
        | for                   { PUTS("for stat"); }
        | NEXT st               { PUTS("next"); $$ = genjump(NEXT); }
        | EXIT st               { PUTS("exit"); $$ = genjump(EXIT); }
        | BREAK st              { PUTS("break"); $$ = genjump(BREAK); }
        | CONTINUE st           { PUTS("continue"); $$ = genjump(CONTINUE); }
        | '{' stat_list '}'     { PUTS("{statlist}"); $$ = $2; }
        ;

stat_list:
          stat_list statement   { PUTS("stat_list stat"); $$ = linkum($1, $2); }
        |                       { PUTS("null stat list"); $$ = nullstat; }
        ;

while:
          WHILE '(' conditional ')' optNL       { PUTS("while(cond)"); $$ = $3; }
        ;

for:
          FOR '(' simple_stat ';' conditional ';' simple_stat ')' optNL statement
                { PUTS("for(e;e;e)"); $$ = stat4(FOR, $3, $5, $7, $10); }
        | FOR '(' simple_stat ';'  ';' simple_stat ')' optNL statement
                { PUTS("for(e;e;e)"); $$ = stat4(FOR, $3, nullstat, $6, $9); }
        | FOR '(' VAR IN VAR ')' optNL statement
                { PUTS("for(v in v)"); $$ = stat3(IN, $3, $5, $8); }
        ;

%%