source: mainline/uspace/app/pcc/f77/fcom/gram.expr@ f74ec77

funarglist:
                { $$ = 0; }
        | funargs
        ;

funargs:  expr
                { $$ = mkchain($1, 0); }
        | funargs SCOMMA expr
                { $$ = hookup($1, mkchain($3,0) ); }
        ;


expr:     uexpr
        | SLPAR expr SRPAR      { $$ = $2; }
        | complex_const
        ;

uexpr:    lhs
        | simple_const
        | expr addop expr   %prec SPLUS
                { $$ = mkexpr($2, $1, $3); }
        | expr SSTAR expr
                { $$ = mkexpr(OPSTAR, $1, $3); }
        | expr SSLASH expr
                { $$ = mkexpr(OPSLASH, $1, $3); }
        | expr SPOWER expr
                { $$ = mkexpr(OPPOWER, $1, $3); }
        | addop expr  %prec SSTAR
                { if($1 == OPMINUS)
                        $$ = mkexpr(OPNEG, $2, 0);
                  else  $$ = $2;
                }
        | expr relop expr  %prec SEQ
                { $$ = mkexpr($2, $1, $3); }
        | expr SEQV expr
                { $$ = mkexpr(OPEQV, $1,$3); }
        | expr SNEQV expr
                { $$ = mkexpr(OPNEQV, $1, $3); }
        | expr SOR expr
                { $$ = mkexpr(OPOR, $1, $3); }
        | expr SAND expr
                { $$ = mkexpr(OPAND, $1, $3); }
        | SNOT expr
                { $$ = mkexpr(OPNOT, $2, 0); }
        | expr SCONCAT expr
                { $$ = mkexpr(OPCONCAT, $1, $3); }
        ;

addop:    SPLUS         { $$ = OPPLUS; }
        | SMINUS        { $$ = OPMINUS; }
        ;

relop:    SEQ   { $$ = OPEQ; }
        | SGT   { $$ = OPGT; }
        | SLT   { $$ = OPLT; }
        | SGE   { $$ = OPGE; }
        | SLE   { $$ = OPLE; }
        | SNE   { $$ = OPNE; }
        ;

lhs:     name
                { $$ = mkprim($1, 0, 0, 0); }
        | name SLPAR opt_expr SCOLON opt_expr SRPAR
                { $$ = mkprim($1, 0, $3, $5); }
        | name SLPAR funarglist SRPAR
                { $$ = mkprim($1, mklist($3), 0, 0); }
        | name SLPAR funarglist SRPAR SLPAR opt_expr SCOLON opt_expr SRPAR
                { $$ = mkprim($1, mklist($3), $6, $8); }
        ;

opt_expr:
                { $$ = 0; }
        | expr
        ;

simple:   name
                { if($1->vclass == CLPARAM)
                        $$ = cpexpr($1->b_param.paramval);
                }
        | simple_const
        ;

simple_const:   STRUE   { $$ = mklogcon(1); }
        | SFALSE        { $$ = mklogcon(0); }
        | SHOLLERITH  { $$ = mkstrcon(toklen, token); }
        | SICON { $$ = mkintcon( convci(toklen, token) ); }
        | SRCON { $$ = mkrealcon(TYREAL, convcd(toklen, token)); }
        | SDCON { $$ = mkrealcon(TYDREAL, convcd(toklen, token)); }
        ;

complex_const:  SLPAR uexpr SCOMMA uexpr SRPAR
                { $$ = mkcxcon($2,$4); }
        ;

bit_const:  SHEXCON
                { $$ = mkbitcon(4, toklen, token); }
        | SOCTCON
                { $$ = mkbitcon(3, toklen, token); }
        | SBITCON
                { $$ = mkbitcon(1, toklen, token); }
        ;

fexpr:    unpar_fexpr
        | SLPAR fexpr SRPAR
                { $$ = $2; }
        ;

unpar_fexpr:      lhs
        | simple_const
        | fexpr addop fexpr   %prec SPLUS
                { $$ = mkexpr($2, $1, $3); }
        | fexpr SSTAR fexpr
                { $$ = mkexpr(OPSTAR, $1, $3); }
        | fexpr SSLASH fexpr
                { $$ = mkexpr(OPSLASH, $1, $3); }
        | fexpr SPOWER fexpr
                { $$ = mkexpr(OPPOWER, $1, $3); }
        | addop fexpr  %prec SSTAR
                { if($1 == OPMINUS)
                        $$ = mkexpr(OPNEG, $2, 0);
                  else  $$ = $2;
                }
        | fexpr SCONCAT fexpr
                { $$ = mkexpr(OPCONCAT, $1, $3); }
        ;