Filters are used to require nouns to have specific kinds or attributes, or to have specific scoping rules: they correspond to Inform 6's |noun=Routine| and |scope=Routine| tokens. Though these are quite different concepts in I6, their common handling seems natural in I7.
typedef struct noun_filter_token { struct parse_node *the_filter; struct parse_node *nft_created_at; int global_scope_flag; int any_things_flag; int parse_using_gpr; int nft_compiled; struct inter_name *nft_iname; CLASS_DEFINITION } noun_filter_token;
- The structure noun_filter_token is private to this section.
§2. There are only three things we can do with these: create them, compile their names (used as I6 tokens), and compile their routines.
noun_filter_token *UnderstandFilterTokens::nft_new(parse_node *spec, int global_scope, int any_things) { pcalc_prop *prop = Specifications::to_proposition(spec); if ((prop) && (Binding::number_free(prop) != 1)) { LOG("So $P and $D\n", spec, prop); StandardProblems::sentence_problem(Task::syntax_tree(), _p_(PM_FilterQuantified), "the [any ...] doesn't clearly give a description in the '...' part", "where I was expecting something like '[any vehicle]'."); spec = Specifications::from_kind(K_object); } noun_filter_token *nft = CREATE(noun_filter_token); nft->the_filter = spec; nft->global_scope_flag = global_scope; nft->any_things_flag = any_things; nft->nft_created_at = current_sentence; nft->parse_using_gpr = FALSE; nft->nft_compiled = FALSE; if (global_scope) { package_request *PR = Hierarchy::local_package(SCOPE_FILTERS_HAP); nft->nft_iname = Hierarchy::make_iname_in(SCOPE_FILTER_FN_HL, PR); } else { package_request *PR = Hierarchy::local_package(NOUN_FILTERS_HAP); nft->nft_iname = Hierarchy::make_iname_in(NOUN_FILTER_FN_HL, PR); } return nft; } inter_name *UnderstandFilterTokens::nft_compile_routine_iname(noun_filter_token *nft) { return nft->nft_iname; } void UnderstandFilterTokens::nft_compile_routine(noun_filter_token *nft) { parse_node *noun_var = Lvalues::new_actual_NONLOCAL_VARIABLE(Inter_noun_VAR); kind *R = Specifications::to_kind(nft->the_filter); kind *K = NonlocalVariables::kind(Inter_noun_VAR); NonlocalVariables::set_kind(Inter_noun_VAR, R); if (Kinds::Behaviour::is_object(R) == FALSE) nft->parse_using_gpr = TRUE; packaging_state save = Routines::begin(nft->nft_iname); if (nft->parse_using_gpr) { inter_symbol *v_s = LocalVariables::add_internal_local_c_as_symbol(I"v", "value parsed"); inter_symbol *n_s = LocalVariables::add_internal_local_c_as_symbol(I"n", "saved value of noun"); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_symbol(Emit::tree(), K_value, v_s); inter_name *gpr_to_ask = Kinds::Behaviour::get_explicit_I6_GPR_iname(R); if (gpr_to_ask == NULL) gpr_to_ask = RTKinds::get_kind_GPR_iname(R); Produce::inv_call_iname(Emit::tree(), gpr_to_ask); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), IF_BIP); Produce::down(Emit::tree()); Produce::inv_primitive(Emit::tree(), EQ_BIP); Produce::down(Emit::tree()); Produce::val_symbol(Emit::tree(), K_value, v_s); Produce::val_iname(Emit::tree(), K_object, Hierarchy::find(GPR_NUMBER_HL)); Produce::up(Emit::tree()); Produce::code(Emit::tree()); Produce::down(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_symbol(Emit::tree(), K_value, n_s); Produce::val_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::val_iname(Emit::tree(), K_object, Hierarchy::find(PARSED_NUMBER_HL)); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), IF_BIP); Produce::down(Emit::tree()); Produce::inv_primitive(Emit::tree(), NOT_BIP); Produce::down(Emit::tree()); Calculus::Deferrals::emit_test_if_var_matches_description(noun_var, nft->the_filter); Produce::up(Emit::tree()); Produce::code(Emit::tree()); Produce::down(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_symbol(Emit::tree(), K_value, v_s); Produce::val_iname(Emit::tree(), K_object, Hierarchy::find(GPR_FAIL_HL)); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::val_symbol(Emit::tree(), K_value, n_s); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), RETURN_BIP); Produce::down(Emit::tree()); Produce::val_symbol(Emit::tree(), K_value, v_s); Produce::up(Emit::tree()); } else if (nft->global_scope_flag) { inter_symbol *obj_s = LocalVariables::add_internal_local_c_as_symbol(I"obj", "object loop variable"); inter_symbol *o2_s = LocalVariables::add_internal_local_c_as_symbol(I"o2", "saved value of noun"); Produce::inv_primitive(Emit::tree(), SWITCH_BIP); Produce::down(Emit::tree()); Produce::val_iname(Emit::tree(), K_object, Hierarchy::find(SCOPE_STAGE_HL)); Produce::code(Emit::tree()); Produce::down(Emit::tree()); Produce::inv_primitive(Emit::tree(), CASE_BIP); Produce::down(Emit::tree()); Produce::val(Emit::tree(), K_number, LITERAL_IVAL, 1); Produce::code(Emit::tree()); Produce::down(Emit::tree()); if (nft->any_things_flag) Produce::rtrue(Emit::tree()); else Produce::rfalse(Emit::tree()); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), CASE_BIP); Produce::down(Emit::tree()); Produce::val(Emit::tree(), K_number, LITERAL_IVAL, 2); Produce::code(Emit::tree()); Produce::down(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_symbol(Emit::tree(), K_value, obj_s); Produce::val_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), OBJECTLOOP_BIP); Produce::down(Emit::tree()); Produce::ref_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::val_iname(Emit::tree(), K_value, RTKinds::I6_classname(K_object)); Calculus::Deferrals::emit_test_if_var_matches_description(noun_var, nft->the_filter); Produce::code(Emit::tree()); Produce::down(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_symbol(Emit::tree(), K_value, o2_s); Produce::val_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::val_symbol(Emit::tree(), K_value, obj_s); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_iname(Emit::tree(), K_object, Hierarchy::find(SUPPRESS_SCOPE_LOOPS_HL)); Produce::val(Emit::tree(), K_truth_state, LITERAL_IVAL, 1); Produce::up(Emit::tree()); Produce::inv_call_iname(Emit::tree(), Hierarchy::find(PLACEINSCOPE_HL)); Produce::down(Emit::tree()); Produce::val_symbol(Emit::tree(), K_value, o2_s); Produce::val(Emit::tree(), K_truth_state, LITERAL_IVAL, 1); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_iname(Emit::tree(), K_object, Hierarchy::find(SUPPRESS_SCOPE_LOOPS_HL)); Produce::val(Emit::tree(), K_truth_state, LITERAL_IVAL, 0); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::val_symbol(Emit::tree(), K_value, o2_s); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::val_symbol(Emit::tree(), K_value, obj_s); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), CASE_BIP); Produce::down(Emit::tree()); Produce::val(Emit::tree(), K_number, LITERAL_IVAL, 3); Produce::code(Emit::tree()); Produce::down(Emit::tree()); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_iname(Emit::tree(), K_object, Hierarchy::find(NEXTBEST_ETYPE_HL)); Produce::val_iname(Emit::tree(), K_object, Hierarchy::find(NOTINCONTEXTPE_HL)); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), RETURN_BIP); Produce::down(Emit::tree()); Produce::val(Emit::tree(), K_number, LITERAL_IVAL, (inter_ti) (-1)); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::up(Emit::tree()); Produce::up(Emit::tree()); } else { inter_symbol *x_s = LocalVariables::add_internal_local_c_as_symbol(I"x", "saved value of noun"); Produce::inv_primitive(Emit::tree(), STORE_BIP); Produce::down(Emit::tree()); Produce::ref_symbol(Emit::tree(), K_value, x_s); Produce::val_iname(Emit::tree(), K_object, Hierarchy::find(NOUN_HL)); Produce::up(Emit::tree()); Produce::inv_primitive(Emit::tree(), RETURN_BIP); Produce::down(Emit::tree()); if (Specifications::to_proposition(nft->the_filter)) { Propositions::Checker::type_check(Specifications::to_proposition(nft->the_filter), Propositions::Checker::tc_no_problem_reporting()); Calculus::Deferrals::emit_test_of_proposition( noun_var, Specifications::to_proposition(nft->the_filter)); } else Calculus::Deferrals::emit_test_if_var_matches_description(noun_var, nft->the_filter); Produce::up(Emit::tree()); } Routines::end(save); NonlocalVariables::set_kind(Inter_noun_VAR, K); }
§3. Access via ID. For now, though, these are perhaps strangely accessed by ID number. (Because the parse_node structure can't conveniently be annotated with pointers, that's why.)
int too_late_for_further_NFTs = FALSE; int UnderstandFilterTokens::new_id(parse_node *spec, int global_scope, int any_things) { if (too_late_for_further_NFTs) StandardProblems::sentence_problem(Task::syntax_tree(), _p_(BelievedImpossible), "complicated instructions on understanding the player's command " "are not allowed in the past tense", "for instance by being applied to several previous turns in a row."); kind *K = Specifications::to_kind(spec); if ((Kinds::Behaviour::is_object(K) == FALSE) && (Kinds::Behaviour::request_I6_GPR(K) == FALSE) && (global_scope)) StandardProblems::sentence_problem(Task::syntax_tree(), _p_(BelievedImpossible), "this is a kind of value I can't understand in command grammar", "so the '[any ...]' part will have to go."); return UnderstandFilterTokens::nft_new(spec, global_scope, any_things)->allocation_id; } void UnderstandFilterTokens::compile_id(int id) { noun_filter_token *nft; LOOP_OVER(nft, noun_filter_token) if (nft->allocation_id == id) { if (nft->parse_using_gpr) Produce::val_iname(Emit::tree(), K_value, Hierarchy::find(GPR_TT_HL)); else if (nft->global_scope_flag) Produce::val_iname(Emit::tree(), K_value, Hierarchy::find(SCOPE_TT_HL)); else Produce::val_iname(Emit::tree(), K_value, Hierarchy::find(ROUTINEFILTER_TT_HL)); Produce::val_iname(Emit::tree(), K_value, nft->nft_iname); } } void UnderstandFilterTokens::emit_id(int id) { noun_filter_token *nft; LOOP_OVER(nft, noun_filter_token) if (nft->allocation_id == id) { inter_ti annot = 0; if (nft->parse_using_gpr == FALSE) { if (nft->global_scope_flag) annot = SCOPE_FILTER_IANN; else annot = NOUN_FILTER_IANN; } inter_name *iname = UnderstandFilterTokens::nft_compile_routine_iname(nft); if (annot != 0) if (Produce::read_annotation(iname, annot) != 1) Produce::annotate_i(iname, annot, 1); Emit::array_iname_entry(iname); } }
§4. Compiling everything. Having referred to these filter routines, we need to compile them.
void UnderstandFilterTokens::compile(void) { noun_filter_token *nft; LOOP_OVER(nft, noun_filter_token) if (nft->nft_compiled == FALSE) { current_sentence = nft->nft_created_at; UnderstandFilterTokens::nft_compile_routine(nft); nft->nft_compiled = TRUE; } too_late_for_further_NFTs = TRUE; }