To compile the instances submodule for a compilation unit, which contains _instance packages.

• §1. Compilation data
• §2. Compilation
• §4. Condition element

§1. Compilation data. Each instance object contains this data:

typedef struct instance_compilation_data {
    struct package_request *instance_package;
    struct inter_name *instance_iname;
    int declaration_sequence_number;
} instance_compilation_data;

instance_compilation_data RTInstances::new_compilation_data(instance *I) {
    instance_compilation_data icd;
    icd.instance_package = Hierarchy::local_package(INSTANCES_HAP);
    wording W = Nouns::nominative(I->as_noun, FALSE);
    icd.instance_iname = Hierarchy::make_iname_with_memo(INSTANCE_HL,
        icd.instance_package, W);
    icd.declaration_sequence_number = -1;
    NounIdentifiers::set_iname(I->as_noun, icd.instance_iname);
    return icd;
}

inter_name *RTInstances::value_iname?Usage of RTInstances::value_iname:
§3, §4
Default Values - §2.4
Instance Counting - §8
Short Names - §4.1
List Literals - §7.2
Stored Action Literals - §1
Backdrop Instances - §2.1
Door Instances - §3, §5, §6
Region Instances - §2
Kind Constructors - §11.3.3
Test Scripts - §4
The Player - §1
The Map - §1, §2
Property Permissions - §1, §3
Tokens Parsing Values - §1.1(instance *I) {
    if (I == NULL) return NULL;
    return I->compilation_data.instance_iname;
}

package_request *RTInstances::package?Usage of RTInstances::package:
§3
Short Names - §3
Backdrop Instances - §1
Door Instances - §2, §4, §6
Region Instances - §1
Scene Instances - §3, §7
Multimedia - §1, §2.3
Property Permissions - §1(instance *I) {
    return I->compilation_data.instance_package;
}

• The structure instance_compilation_data is accessed in 5/kc and here.

§2. Compilation.

int RTInstances::compile_all(inference_subject_family *family, int ignored) {
    Number instances in declaration order2.1;
    instance *I;
    LOOP_OVER(I, instance) {
        text_stream *desc = Str::new();
        WRITE_TO(desc, "instance "); Instances::write(desc, I);
        Sequence::queue(&RTInstances::compilation_agent, STORE_POINTER_instance(I), desc);
    }
    return TRUE;
}

§2.1. The code here assigns each instance I a sequence number in such a way that the object instances come out in a well-founded order spatially — that is, so that each object X is followed immediately by its children (i.e., the objects inside or on top of it).

This will be used to annotate the Inter tree so that the declaration order can be recovered in code-generation, when it would otherwise be lost as the various instances scatter all over the tree.

Number instances in declaration order2.1 =

    instance *I;
    int n = 0;
    LOOP_THROUGH_INSTANCE_ORDERING(I)
        I->compilation_data.declaration_sequence_number = n++;
    LOOP_OVER(I, instance)
        if (Kinds::Behaviour::is_object(Instances::to_kind(I)) == FALSE)
            I->compilation_data.declaration_sequence_number = n++;

• This code is used in §2.

§3. This is really all metadata except for the actual instance declaration, using Inter's INSTANCE_IST instruction.

void RTInstances::compilation_agent?Usage of RTInstances::compilation_agent:
§2(compilation_subtask *t) {
    instance *I = RETRIEVE_POINTER_instance(t->data);
    package_request *pack = I->compilation_data.instance_package;
    Hierarchy::apply_metadata_from_wording(pack, INSTANCE_NAME_MD_HL,
        Nouns::nominative(I->as_noun, FALSE));
    Hierarchy::apply_metadata_from_iname(pack, INSTANCE_VALUE_MD_HL, I->compilation_data.instance_iname);
    inter_name *kn_iname = Hierarchy::make_iname_in(INSTANCE_KIND_MD_HL, pack);
    kind *K = Instances::to_kind(I);
    RTKindIDs::define_constant_as_strong_id(kn_iname, K);
    if ((K_scene) && (Kinds::eq(K, K_scene)))
        Hierarchy::apply_metadata_from_number(pack,
            INSTANCE_IS_SCENE_MD_HL, 1);
    if ((K_sound_name) && (Kinds::eq(K, K_sound_name)))
        Hierarchy::apply_metadata_from_number(pack,
            INSTANCE_IS_SOUND_MD_HL, 1);
    if ((K_figure_name) && (Kinds::eq(K, K_figure_name)))
        Hierarchy::apply_metadata_from_number(pack,
            INSTANCE_IS_FIGURE_MD_HL, 1);
    if ((K_external_file) && (Kinds::eq(K, K_external_file)))
        Hierarchy::apply_metadata_from_number(pack,
            INSTANCE_IS_EXF_MD_HL, 1);

    if (RTShowmeCommand::needed_for_instance(I)) {
        inter_name *iname = Hierarchy::make_iname_in(INST_SHOWME_FN_HL,
            RTInstances::package(I));
        RTShowmeCommand::compile_instance_showme_fn(iname, I);
        Hierarchy::apply_metadata_from_iname(RTInstances::package(I),
            INST_SHOWME_MD_HL, iname);
    }

    Emit::instance(RTInstances::value_iname(I), Instances::to_kind(I), I->enumeration_index);
    if (I->compilation_data.declaration_sequence_number >= 0)
        Produce::annotate_i(RTInstances::value_iname(I), DECLARATION_ORDER_IANN,
            (inter_ti) I->compilation_data.declaration_sequence_number);
    RTPropertyPermissions::compile_permissions_for_instance(I);
    RTPropertyValues::compile_values_for_instance(I);

    if (Kinds::Behaviour::is_object(Instances::to_kind(I))) {
        int AC = Spatial::get_definition_depth(I);
        if (AC > 0) Produce::annotate_i(RTInstances::value_iname(I), ARROW_COUNT_IANN,
            (inter_ti) AC);
    }

    RTRegionInstances::compile_extra(I);
    RTBackdropInstances::compile_extra(I);
    RTScenes::compile_extra(I);
}

§4. Condition element. This compiles a test of whether or not t0_s is equal to an instance.

int RTInstances::emit_element_of_condition(inference_subject_family *family,
    inference_subject *infs, inter_symbol *t0_s) {
    instance *I = InstanceSubjects::to_instance(infs);
    EmitCode::inv(EQ_BIP);
    EmitCode::down();
        EmitCode::val_symbol(K_value, t0_s);
        EmitCode::val_iname(K_value, RTInstances::value_iname(I));
    EmitCode::up();
    return TRUE;
}