X-Git-Url: https://git.m6w6.name/?p=m6w6%2Fext-psi;a=blobdiff_plain;f=src%2Fparser_proc.y;h=4d96acb6f86fb785698fbf440bc35b04c20cc72e;hp=b97d28f7b00e4dfc23cd29c4a80abed630a62dc0;hb=898c6dac30d12d7fe56662d66a8e73c340926d64;hpb=b25cb3852e3c6ef6da608001585218015aaf5d3e diff --git a/src/parser_proc.y b/src/parser_proc.y index b97d28f..4d96acb 100644 --- a/src/parser_proc.y +++ b/src/parser_proc.y @@ -13,24 +13,18 @@ #include "parser.h" } -%include {void psi_error(int, const char *, int, const char *, ...);} - - - +%include { void psi_error(int, const char *, int, const char *, ...); } %name psi_parser_proc_ %token_prefix PSI_T_ %token_type {struct psi_token *} %token_destructor {free($$);} %default_destructor {(void)P;} %extra_argument {struct psi_parser *P} - - -%syntax_error { ++P->errors; if (TOKEN && TOKEN->type != PSI_T_EOF) { psi_error(PSI_WARNING, TOKEN->file, TOKEN->line, "PSI syntax error: Unexpected token '%s' at pos %u", TOKEN->text, TOKEN->col); } else { psi_error(PSI_WARNING, P->psi.file.fn, P->line, "PSI syntax error: Unexpected end of input"); }} +%syntax_error { ++P->errors; if (TOKEN && TOKEN->type != PSI_T_EOF) { psi_error(PSI_WARNING, TOKEN->file, TOKEN->line, "PSI syntax error: Unexpected token '%s' at pos %u", TOKEN->text, TOKEN->col); } else { psi_error(PSI_WARNING, P->psi.file.fn, P->line, "PSI syntax error: Unexpected end of input"); } } %nonassoc NAME. %left PLUS MINUS. %left SLASH ASTERISK. %fallback NAME TEMP FREE SET LET RETURN CALLOC CALLBACK ZVAL LIB STRING. - %token_class const_type_token BOOL INT FLOAT STRING. %token_class decl_type_token FLOAT DOUBLE INT8 UINT8 INT16 UINT16 INT32 UINT32 INT64 UINT64 NAME. %token_class impl_def_val_token NULL NUMBER TRUE FALSE QUOTED_STRING. @@ -39,7 +33,6 @@ %token_class let_func_token ZVAL OBJVAL ARRVAL PATHVAL STRLEN STRVAL FLOATVAL INTVAL BOOLVAL. %token_class set_func_token TO_OBJECT TO_ARRAY TO_STRING TO_INT TO_FLOAT TO_BOOL ZVAL VOID. %token_class impl_type_token VOID MIXED BOOL INT FLOAT STRING ARRAY OBJECT CALLABLE. - %type decl_enum {decl_enum *} %destructor decl_enum {free_decl_enum($$);} %type decl_enum_items {decl_enum_items*} @@ -148,14 +141,11 @@ %type reference {char} %type indirection {unsigned} %type pointers {unsigned} - file ::= blocks. blocks ::= block. blocks ::= blocks block. - block ::= EOF. block ::= EOS. - block ::= LIB(token) QUOTED_STRING(libname) EOS. { if (P->psi.file.ln) { P->error(P, token, PSI_WARNING, "Extra 'lib %s' statement has no effect", libname->text); @@ -168,11 +158,9 @@ block ::= LIB(token) QUOTED_STRING(libname) EOS. { block ::= decl(decl). { P->decls = add_decl(P->decls, decl); } - block ::= impl(impl). { P->impls = add_impl(P->impls, impl); } - block ::= decl_typedef(def). { P->defs = add_decl_typedef(P->defs, def); switch (def->type->type) { @@ -193,192 +181,116 @@ block ::= decl_typedef(def). { break; } } - block ::= constant(constant). { P->consts = add_constant(P->consts, constant); } - block ::= decl_struct(strct). { P->structs = add_decl_struct(P->structs, strct); } - block ::= decl_union(u). { P->unions = add_decl_union(P->unions, u); } - block ::= decl_enum(e). { P->enums = add_decl_enum(P->enums, e); } - optional_name(n) ::= . { n = NULL; } - optional_name(n) ::= NAME(N). { - n = N; } - enum_name(n) ::= ENUM(E) optional_name(N). { - if (N) { n = N; free(E); } else { char digest[17]; - psi_token_hash(E, digest); n = psi_token_translit(psi_token_append(E, 1, digest), " ", "@"); } } - decl_enum(e) ::= enum_name(N) LBRACE decl_enum_items(list) RBRACE. { - - - - e = init_decl_enum(N->text, list); e->token = N; } - decl_enum_items(l) ::= decl_enum_item(i). { - l = init_decl_enum_items(i); } decl_enum_items(l) ::= decl_enum_items(l_) COMMA decl_enum_item(i). { - - - l = add_decl_enum_item(l_, i); } - decl_enum_item(i) ::= NAME(N) EQUALS num_exp(num). { - - - i = init_decl_enum_item(N->text, num); i->token = N; } decl_enum_item(i) ::= NAME(N). { - i = init_decl_enum_item(N->text, NULL); i->token = N; } - union_name(n) ::= UNION(U) optional_name(N). { - - if (N) { n = N; free(U); } else { char digest[17]; - psi_token_hash(U, digest); n = psi_token_translit(psi_token_append(U, 1, digest), " ", "@"); } } - struct_name(n) ::= STRUCT(S) optional_name(N). { - - if (N) { n = N; free(S); } else { char digest[17]; - psi_token_hash(S, digest); n = psi_token_translit(psi_token_append(S, 1, digest), " ", "@"); } } - decl_struct_args_block(args_) ::= LBRACE struct_args(args) RBRACE. { - - - args_ = args; } - decl_struct_args(args_) ::= decl_struct_args_block(args). { - args_ = args; } decl_struct_args(args_) ::= EOS. { - args_ = init_decl_args(NULL); } - decl_struct(strct) ::= STRUCT NAME(N) align_and_size(as) decl_struct_args(args). { - - - - strct = init_decl_struct(N->text, args); strct->align = as.pos; strct->size = as.len; strct->token = N; } - align_and_size(as) ::= . { as.pos = 0; as.len = 0; } align_and_size(as) ::= COLON COLON LPAREN NUMBER(A) COMMA NUMBER(S) RPAREN. { - - - - - - - as.pos = atol(A->text); as.len = atol(S->text); free(A); free(S); } - decl_union(u) ::= UNION NAME(N) align_and_size(as) decl_struct_args(args). { - - - - u = init_decl_union(N->text, args); u->align = as.pos; u->size = as.len; u->token = N; } - const_type(type_) ::= const_type_token(T). { - type_ = init_const_type(T->type, T->text); free(T); } - constant(constant) ::= CONST const_type(type) NSNAME(T) EQUALS impl_def_val(val) EOS. { - - - - - - constant = init_constant(type, T->text, val); free(T); } - decl_typedef(def) ::= TYPEDEF(T) decl_typedef_body(def_) EOS. { - - - def = def_; def->token = T; } - decl_typedef_body_ex(def) ::= struct_name(N) align_and_size(as) decl_struct_args_block(args) decl_var(var). { - - - - def = init_decl_arg(init_decl_type(PSI_T_STRUCT, N->text), var); def->type->token = psi_token_copy(N); def->type->real.strct = init_decl_struct(N->text, args); @@ -387,10 +299,6 @@ decl_typedef_body_ex(def) ::= struct_name(N) align_and_size(as) decl_struct_args def->type->real.strct->size = as.len; } decl_typedef_body_ex(def) ::= union_name(N) align_and_size(as) decl_struct_args_block(args) decl_var(var). { - - - - def = init_decl_arg(init_decl_type(PSI_T_UNION, N->text), var); def->type->token = psi_token_copy(N); def->type->real.unn = init_decl_union(N->text, args); @@ -399,55 +307,32 @@ decl_typedef_body_ex(def) ::= union_name(N) align_and_size(as) decl_struct_args_ def->type->real.unn->size = as.len; } decl_typedef_body_ex(def) ::= decl_enum(e) NAME(ALIAS). { - - def = init_decl_arg(init_decl_type(PSI_T_ENUM, e->name), init_decl_var(ALIAS->text, 0, 0)); def->var->token = ALIAS; def->type->token = psi_token_copy(e->token); def->type->real.enm = e; } - decl_typedef_body(def) ::= decl_typedef_body_ex(def_). { - def = def_; } - decl_typedef_body_fn_args(args) ::= LPAREN decl_args(args_) RPAREN. { - - - args = args_; } decl_typedef_body(def) ::= decl_func(func_) decl_typedef_body_fn_args(args). { - - def = init_decl_arg(init_decl_type(PSI_T_FUNCTION, func_->var->name), copy_decl_var(func_->var)); def->type->token = psi_token_copy(func_->token); def->type->real.func = init_decl(init_decl_abi("default"), func_, args); } decl_typedef_body(def) ::= decl_arg(arg). { - def = arg; } - decl(decl) ::= decl_abi(abi) decl_func(func) LPAREN decl_args(args) RPAREN EOS. { - - - - - - decl = init_decl(abi, func, args); } - decl_func(func) ::= decl_arg(arg). { - func = arg; } - decl_func(func) ::= VOID(T) NAME(N). { - - func = init_decl_arg( init_decl_type(T->type, T->text), init_decl_var(N->text, 0, 0) @@ -457,13 +342,6 @@ decl_func(func) ::= VOID(T) NAME(N). { func->token = N; } decl_typedef_body(def) ::= VOID(T) indirection(decl_i) LPAREN indirection(type_i) NAME(N) RPAREN decl_typedef_body_fn_args(args). { - - - - - - - decl_arg *func_ = init_decl_arg( init_decl_type(T->type, T->text), init_decl_var(N->text, decl_i, 0) @@ -471,7 +349,6 @@ decl_typedef_body(def) ::= VOID(T) indirection(decl_i) LPAREN indirection(type_i func_->type->token = T; func_->var->token = N; func_->token = N; - def = init_decl_arg( init_decl_type(PSI_T_FUNCTION, func_->var->name), copy_decl_var(func_->var) @@ -488,7 +365,6 @@ decl_typedef_body(def) ::= CONST VOID(T) pointers(decl_i) LPAREN indirection(typ func_->type->token = T; func_->var->token = N; func_->token = N; - def = init_decl_arg( init_decl_type(PSI_T_FUNCTION, func_->var->name), copy_decl_var(func_->var) @@ -497,61 +373,35 @@ decl_typedef_body(def) ::= CONST VOID(T) pointers(decl_i) LPAREN indirection(typ def->type->token = psi_token_copy(func_->token); def->type->real.func = init_decl(init_decl_abi("default"), func_, args); } - decl_abi(abi) ::= NAME(T). { - abi = init_decl_abi(T->text); abi->token = T; } - decl_var(var) ::= indirection(p) NAME(T). { - - var = init_decl_var(T->text, p, 0); var->token = T; } decl_var(var) ::= indirection(p) NAME(T) LBRACKET NUMBER(D) RBRACKET. { - - - - - var = init_decl_var(T->text, p+1, atol(D->text)); var->token = T; free(D); } - decl_vars(vars) ::= decl_var(var). { - vars = init_decl_vars(var); } decl_vars(vars) ::= decl_vars(vars_) COMMA decl_var(var). { - - - vars = add_decl_var(vars_, var); } - decl_arg(arg_) ::= const_decl_type(type) decl_var(var). { - - arg_ = init_decl_arg(type, var); } decl_typedef_body(def) ::= const_decl_type(type_) indirection(decl_i) LPAREN indirection(type_i) NAME(N) RPAREN decl_typedef_body_fn_args(args). { - - - - - - - decl_arg *func_ = init_decl_arg( type_, init_decl_var(N->text, decl_i, 0) ); func_->var->token = N; func_->token = N; - def = init_decl_arg( init_decl_type(PSI_T_FUNCTION, func_->var->name), copy_decl_var(func_->var) @@ -560,12 +410,7 @@ decl_typedef_body(def) ::= const_decl_type(type_) indirection(decl_i) LPAREN ind def->type->token = psi_token_copy(func_->token); def->type->real.func = init_decl(init_decl_abi("default"), func_, args); } - - decl_arg(arg_) ::= VOID(T) pointers(p) NAME(N). { - - - arg_ = init_decl_arg( init_decl_type(T->type, T->text), init_decl_var(N->text, p, 0) @@ -575,10 +420,6 @@ decl_arg(arg_) ::= VOID(T) pointers(p) NAME(N). { arg_->token = N; } decl_arg(arg_) ::= CONST VOID(T) pointers(p) NAME(N). { - - - - arg_ = init_decl_arg( init_decl_type(T->type, T->text), init_decl_var(N->text, p, 0) @@ -587,40 +428,25 @@ decl_arg(arg_) ::= CONST VOID(T) pointers(p) NAME(N). { arg_->var->token = N; arg_->token = N; } - decl_args ::= . decl_args ::= VOID. decl_args(args) ::= decl_arg(arg). { - args = init_decl_args(arg); } decl_args(args) ::= decl_args(args_) COMMA decl_arg(arg). { - - - args = add_decl_arg(args_, arg); } decl_args(args) ::= decl_args(args_) COMMA ELLIPSIS. { - - - args = args_; args->varargs = 1; } - struct_args(args) ::= struct_arg(arg). { - args = init_decl_args(arg); } struct_args(args) ::= struct_args(args_) struct_arg(arg). { - - args = add_decl_arg(args_, arg); } - struct_arg(arg_) ::= decl_typedef_body_ex(def) EOS. { - - arg_ = def; switch (def->type->type) { case PSI_T_STRUCT: @@ -641,37 +467,21 @@ struct_arg(arg_) ::= decl_typedef_body_ex(def) EOS. { } } struct_arg(arg) ::= decl_arg(arg_) struct_layout(layout_) EOS. { - - - arg_->layout = layout_; arg = arg_; } - struct_layout(layout) ::= . { layout = NULL; } struct_layout(layout) ::= COLON COLON LPAREN NUMBER(POS) COMMA NUMBER(SIZ) RPAREN. { - - - - - - - layout = init_decl_struct_layout(atol(POS->text), atol(SIZ->text)); free(POS); free(SIZ); } - - decl_scalar_type(type_) ::= CHAR(C). { - type_ = C; } decl_scalar_type(type_) ::= SHORT(S) decl_scalar_type_short(s). { - - if (s) { type_ = psi_token_cat(2, S, s); free(S); @@ -683,18 +493,13 @@ decl_scalar_type(type_) ::= SHORT(S) decl_scalar_type_short(s). { decl_scalar_type_short(s) ::= . { s = NULL; } - decl_scalar_type_short(s) ::= INT(I). { - s = I; } decl_scalar_type(type_) ::= INT(I). { - type_ = I; } decl_scalar_type(type_) ::= LONG(L) decl_scalar_type_long(l). { - - if (l) { type_ = psi_token_cat(2, L, l); free(L); @@ -707,12 +512,9 @@ decl_scalar_type_long(l) ::= . { l = NULL; } decl_scalar_type_long(l) ::= DOUBLE(D). { - l = D; } decl_scalar_type_long(l) ::= LONG(L) decl_scalar_type_long_long(ll). { - - if (ll) { l = psi_token_cat(2, L, ll); free(L); @@ -725,12 +527,9 @@ decl_scalar_type_long_long(ll) ::= . { ll = NULL; } decl_scalar_type_long_long(ll) ::= INT(I). { - ll = I; } decl_type(type_) ::= UNSIGNED(U) decl_scalar_type(N). { - - struct psi_token *T = psi_token_cat(2, U, N); type_ = init_decl_type(T->type, T->text); type_->token = T; @@ -738,8 +537,6 @@ decl_type(type_) ::= UNSIGNED(U) decl_scalar_type(N). { free(N); } decl_type(type_) ::= SIGNED(S) decl_scalar_type(N). { - - struct psi_token *T = psi_token_cat(2, S, N); type_ = init_decl_type(T->type, T->text); type_->token = T; @@ -747,298 +544,169 @@ decl_type(type_) ::= SIGNED(S) decl_scalar_type(N). { free(N); } decl_type(type_) ::= UNSIGNED(U). { - type_ = init_decl_type(PSI_T_NAME, U->text); type_->token = U; } decl_type(type_) ::= SIGNED(S). { - type_ = init_decl_type(PSI_T_NAME, S->text); type_->token = S; } decl_type(type_) ::= decl_scalar_type(N). { - type_ = init_decl_type(N->type, N->text); type_->token = N; } - decl_type(type_) ::= STRUCT(S) NAME(T). { - - type_ = init_decl_type(S->type, T->text); type_->token = T; free(S); } decl_type(type_) ::= UNION(U) NAME(T). { - - type_ = init_decl_type(U->type, T->text); type_->token = T; free(U); } decl_type(type_) ::= ENUM(E) NAME(T). { - - type_ = init_decl_type(E->type, T->text); type_->token = T; free(E); } decl_type(type_) ::= decl_type_token(T). { - type_ = init_decl_type(T->type, T->text); type_->token = T; } - - const_decl_type(type) ::= decl_type(type_). { - type = type_; } const_decl_type(type) ::= CONST decl_type(type_). { - - type = type_; } - impl(impl) ::= impl_func(func) LBRACE impl_stmts(stmts) RBRACE. { - - - - impl = init_impl(func, stmts); } - impl_func(func) ::= FUNCTION reference(r) NSNAME(NAME) impl_args(args) COLON impl_type(type). { - - - - - - func = init_impl_func(NAME->text, args, type, r); func->token = NAME; } - impl_def_val(def) ::= impl_def_val_token(T). { - def = init_impl_def_val(T->type, T->text); free(T); } - impl_var(var) ::= reference(r) DOLLAR_NAME(T). { - - var = init_impl_var(T->text, r); var->token = T; } - impl_arg(arg) ::= impl_type(type) impl_var(var). { - - arg = init_impl_arg(type, var, NULL); } impl_arg(arg) ::= impl_type(type) impl_var(var) EQUALS impl_def_val(def). { - - - - arg = init_impl_arg(type, var, def); } - impl_args(args) ::= LPAREN RPAREN. { - - args = NULL; } impl_args(args) ::= LPAREN impl_arg_list(args_) RPAREN. { - - - args = args_; } impl_args(args) ::= LPAREN impl_arg_list(args_) COMMA impl_vararg(va) RPAREN. { - - - - - args = args_; args->vararg.name = va; } - impl_vararg(va) ::= impl_type(type) reference(r) ELLIPSIS DOLLAR_NAME(T). { - - - - va = init_impl_arg(type, init_impl_var(T->text, r), NULL); free(T); } - impl_arg_list(args) ::= impl_arg(arg). { - args = init_impl_args(arg); } impl_arg_list(args) ::= impl_arg_list(args_) COMMA impl_arg(arg). { - - - args = add_impl_arg(args_, arg); } - impl_stmts(stmts) ::= impl_stmt(stmt). { - stmts = init_impl_stmts(stmt); } impl_stmts(stmts) ::= impl_stmts(stmts_) impl_stmt(stmt). { - - stmts = add_impl_stmt(stmts_, stmt); } - impl_stmt(stmt) ::= let_stmt(let). { - stmt = init_impl_stmt(PSI_T_LET, let); } impl_stmt(stmt) ::= set_stmt(set). { - stmt = init_impl_stmt(PSI_T_SET, set); } impl_stmt(stmt) ::= return_stmt(ret). { - stmt = init_impl_stmt(PSI_T_RETURN, ret); } impl_stmt(stmt) ::= free_stmt(free). { - stmt = init_impl_stmt(PSI_T_FREE, free); } - num_exp(exp) ::= num_exp_token(tok). { - exp = init_num_exp(tok->type, tok->text); exp->token = tok; } num_exp(exp) ::= decl_var(var). { - exp = init_num_exp(PSI_T_NAME, var); exp->token = psi_token_copy(var->token); } num_exp(exp) ::= num_exp(exp_) num_exp_op_token(operator_) num_exp(operand_). { - - - exp_->operator = operator_->type; exp_->operand = operand_; exp = exp_; free(operator_); } - let_stmt(let) ::= LET decl_var(var) EOS. { - - - let = init_let_stmt(var, init_let_val(PSI_LET_NULL, NULL)); } let_stmt(let) ::= LET decl_var(var) EQUALS reference(r) let_val(val) EOS. { - - - - - - val->flags.one.is_reference = r ? 1 : 0; let = init_let_stmt(var, val); } let_stmt(let) ::= TEMP decl_var(var) EQUALS decl_var(val) EOS. { - - - - - let = init_let_stmt(var, init_let_val(PSI_LET_TMP, val)); } - let_calloc(alloc) ::= num_exp(nmemb) COMMA num_exp(size). { - - - alloc = init_let_calloc(nmemb, size); } - let_func(func) ::= let_func_token(T) LPAREN impl_var(var) RPAREN. { - - - - func = init_let_func(T->type, T->text, var); free(T); } - let_vals(vals) ::= let_val(val). { - vals = init_let_vals(val); } let_vals(vals) ::= let_vals(vals_) COMMA let_val(val). { - - - vals = add_let_val(vals_, val); } - let_func(func) ::= let_func_token(T) LPAREN impl_var(var) COMMA let_vals(vals) RPAREN. { - - - - - - func = init_let_func(T->type, T->text, var); func->inner = vals; free(T); } - callback_arg_list ::= . callback_arg_list(args) ::= callback_args(args_). { - args = args_; } - callback_args(args) ::= set_value(val). { - args = init_set_values(val); } callback_args(args) ::= callback_args(args_) COMMA set_value(val). { - - - args = add_set_value(args_, val); } callback_rval(rval) ::= let_func_token(F). { - rval = F; } callback_rval(rval) ::= VOID(V). { - rval = V; } - let_val(val) ::= NULL. { - val = init_let_val(PSI_LET_NULL, NULL); } let_val(val) ::= num_exp(exp). { - val = init_let_val(PSI_LET_NUMEXP, exp); } let_val(val) ::= CALLOC LPAREN let_calloc(alloc) RPAREN. { - - - - val = init_let_val(PSI_LET_CALLOC, alloc); } let_val(val) ::= let_func(func_). { - val = init_let_val(PSI_LET_FUNC, func_); } let_val(val) ::= CALLBACK callback_rval(F) LPAREN impl_var(var) LPAREN callback_arg_list(args_) RPAREN RPAREN. { @@ -1046,51 +714,22 @@ let_val(val) ::= CALLBACK callback_rval(F) LPAREN impl_var(var) LPAREN callback_ init_let_func(F->type, F->text, var), args_)); free(F); } - set_stmt(set) ::= SET impl_var(var) EQUALS set_value(val) EOS. { - - - - - set = init_set_stmt(var, val); } - set_value(val) ::= set_func(func) LPAREN decl_var(var) RPAREN. { - - - - val = init_set_value(func, init_decl_vars(var)); } set_value(val) ::= set_func(func) LPAREN decl_var(var) COMMA num_exp(num_) RPAREN. { - - - - - - val = init_set_value(func, init_decl_vars(var)); val->num = num_; } set_value(val) ::= set_func(func_) LPAREN decl_var(var) COMMA ELLIPSIS(T) RPAREN. { - - - - - - free_set_func(func_); val = init_set_value(init_set_func(T->type, T->text), init_decl_vars(var)); val->func->token = T; } set_value(val) ::= set_func(func_) LPAREN decl_var(var) COMMA set_vals(vals) RPAREN. { - - - - - - val = vals; val->func = func_; val->vars = init_decl_vars(var); @@ -1101,87 +740,52 @@ set_value(val) ::= set_func(func_) LPAREN decl_var(var) COMMA num_exp(num_) COMM val->num = num_; val->vars = init_decl_vars(var); } - set_vals(vals) ::= set_value(val). { - vals = add_inner_set_value(init_set_value(NULL, NULL), val); } set_vals(vals) ::= set_vals(vals_) COMMA set_value(val). { - - - vals = add_inner_set_value(vals_, val); } - set_func(func) ::= set_func_token(T). { - func = init_set_func(T->type, T->text); func->token = T; } - return_stmt(ret) ::= RETURN(T) set_value(val) EOS. { - - - ret = init_return_stmt(val); ret->token = T; } - free_stmt(free) ::= FREE free_calls(calls) EOS. { - - - free = init_free_stmt(calls); } - free_calls(calls) ::= free_call(call). { - calls = init_free_calls(call); } free_calls(calls) ::= free_calls(calls_) COMMA free_call(call). { - - - calls = add_free_call(calls_, call); } - free_call(call) ::= NAME(F) LPAREN decl_vars(vars) RPAREN. { - - - - call = init_free_call(F->text, vars); call->token = F; } - impl_type(type_) ::= impl_type_token(T). { - type_ = init_impl_type(T->type, T->text); free(T); } - reference(r) ::= . { r = 0; } reference(r) ::= AMPERSAND. { - r = 1; } - indirection(i) ::= .{ i = 0; } indirection(i) ::= pointers(p). { - i = p; } - pointers(p) ::= ASTERISK. { - p = 1; } pointers(p) ::= pointers(p_) ASTERISK. { - - p = p_+1; }