To compile the activities submodule for a compilation unit, which contains _activity packages.

• §1. Compilation data
• §7. Compilation

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

typedef struct activity_compilation_data {
    int translated;
    struct text_stream *translated_name;
    struct package_request *av_package;  its _activity package
    struct inter_name *value_iname;      an identifier for a constant identifying this
    struct inter_name *translated_iname;  an alias useful for linking purposes
    struct inter_name *variables_id;     ID for the shared variables set, if any
    struct wording av_documentation_symbol;  cross-reference to HTML documentation, if any
    struct activity_crossref *cross_references;
} activity_compilation_data;

typedef struct activity_crossref {
    struct id_body *rule_dependent;
    struct activity_crossref *next;
} activity_crossref;

• The structure activity_compilation_data is accessed in 4/rsp, 5/rls, 5/rlb, 5/prp, 5/act2 and here.
• The structure activity_crossref is accessed in 2/cu, 4/ts, 5/si, 5/tbl, 5/dbi, 5/dli, 5/dci, 5/rls, 5/rlb, 5/lp and here.

§2. Which is created, long before compilation time, thus:

activity_compilation_data RTActivities::new_compilation_data(activity *av, wording doc) {
    activity_compilation_data acd;
    acd.translated = FALSE;
    acd.translated_name = NULL;
    acd.av_package = Hierarchy::local_package(ACTIVITIES_HAP);
    acd.value_iname = Hierarchy::make_iname_with_memo(ACTIVITY_VALUE_HL, acd.av_package, av->name);
    acd.translated_iname = NULL;
    acd.variables_id = Hierarchy::make_iname_in(ACTIVITY_SHV_ID_HL, acd.av_package);
    acd.av_documentation_symbol = doc;
    acd.cross_references = NULL;
    return acd;
}

§3. Regarded as an rvalue, an activity compiles to this:

inter_name *RTActivities::iname(activity *av) {
    return av->compilation_data.value_iname;
}

inter_name *RTActivities::id_translated?Usage of RTActivities::id_translated:
§8(activity *av) {
    if (Str::len(av->compilation_data.translated_name) == 0) return NULL;
    if (av->compilation_data.translated_iname == NULL) {
        av->compilation_data.translated_iname = InterNames::explicitly_named(
            av->compilation_data.translated_name, av->compilation_data.av_package);
        Hierarchy::make_available(av->compilation_data.translated_iname);
    }
    return av->compilation_data.translated_iname;
}

§4. Three subpackages contain its three rulebooks, requested here:

package_request *RTActivities::rulebook_package(activity *av, int N) {
    package_request *pack = av->compilation_data.av_package;
    switch (N) {
        case 0: return Hierarchy::make_package_in(ACTIVITY_BEFORE_RB_HL, pack);
        case 1: return Hierarchy::make_package_in(ACTIVITY_FOR_RB_HL,    pack);
        case 2: return Hierarchy::make_package_in(ACTIVITY_AFTER_RB_HL,  pack);
    }
    internal_error("bad activity rulebook");
    return NULL;
}

§5.

void RTActivities::annotate_list_for_cross_references?Usage of RTActivities::annotate_list_for_cross_references:
Rules - §15.2(activity_list *avl, id_body *idb) {
    for (; avl; avl = avl->next)
        if (avl->activity) {
            activity *av = avl->activity;
            activity_crossref *acr = CREATE(activity_crossref);
            acr->next = av->compilation_data.cross_references;
            av->compilation_data.cross_references = acr;
            acr->rule_dependent = idb;
        }
}

§6.

void RTActivities::translate(activity *av, wording W) {
    if (av->compilation_data.translated) {
        StandardProblems::sentence_problem(Task::syntax_tree(),
            _p_(PM_TranslatesActivityAlready),
            "this activity has already been translated",
            "so there must be some duplication somewhere.");
        return;
    }
    av->compilation_data.translated = TRUE;
    av->compilation_data.translated_name = Str::new();
    WRITE_TO(av->compilation_data.translated_name, "%N", Wordings::first_wn(W));
}

§7. Compilation.

void RTActivities::compile(void) {
    activity *av;
    LOOP_OVER(av, activity) {
        text_stream *desc = Str::new();
        WRITE_TO(desc, "activity '%W'", av->name);
        Sequence::queue(&RTActivities::compilation_agent, STORE_POINTER_activity(av), desc);
    }
}

§8. So the following makes a single _activity package. As noted above, an activity compiles as a value to its value_iname, which will typically have a descriptive name such as V_printing_short_title. But this is equated below to another constant in the same package, always called activity_id. Those ID numbers must all be distinct at runtime, and this is arranged during linking: for now, we simply write 0.

void RTActivities::compilation_agent?Usage of RTActivities::compilation_agent:
§7(compilation_subtask *t) {
    activity *av = RETRIEVE_POINTER_activity(t->data);
    package_request *pack = av->compilation_data.av_package;
    inter_name *iname = Hierarchy::make_iname_in(ACTIVITY_ID_HL, pack);
    Emit::numeric_constant(iname, 0);  a placeholder: see above
    inter_name *translated = RTActivities::id_translated(av);
    if (translated) Emit::iname_constant(translated, K_value, iname);

    Emit::iname_constant(av->compilation_data.value_iname, K_value, iname);

    Hierarchy::apply_metadata_from_wording(pack, ACTIVITY_NAME_MD_HL, av->name);
    Hierarchy::apply_metadata_from_number(pack, ACTIVITY_AT_MD_HL,
        (inter_ti) Wordings::first_wn(av->name));

    Hierarchy::apply_metadata_from_iname(pack, ACTIVITY_BEFORE_MD_HL,
        RTRulebooks::id_iname(av->before_rules));
    Hierarchy::apply_metadata_from_iname(pack, ACTIVITY_FOR_MD_HL,
        RTRulebooks::id_iname(av->for_rules));
    Hierarchy::apply_metadata_from_iname(pack, ACTIVITY_AFTER_MD_HL,
        RTRulebooks::id_iname(av->after_rules));
    Hierarchy::apply_metadata_from_number(pack, ACTIVITY_UFA_MD_HL,
        (inter_ti) Activities::used_by_future_actions(av));
    Hierarchy::apply_metadata_from_number(pack, ACTIVITY_HID_MD_HL,
        (inter_ti) Activities::hide_in_debugging(av));

    int empty = TRUE;
    if (Rulebooks::is_empty(av->before_rules) == FALSE) empty = FALSE;
    if (Rulebooks::is_empty(av->for_rules) == FALSE) empty = FALSE;
    if (Rulebooks::is_empty(av->after_rules) == FALSE) empty = FALSE;
    Hierarchy::apply_metadata_from_number(pack, ACTIVITY_EMPTY_MD_HL,
        (inter_ti) empty);
    if (Wordings::nonempty(av->compilation_data.av_documentation_symbol))
        Hierarchy::apply_metadata_from_raw_wording(pack, ACTIVITY_DOCUMENTATION_MD_HL,
            Wordings::one_word(Wordings::first_wn(av->compilation_data.av_documentation_symbol)));

    if (SharedVariables::set_empty(av->activity_variables) == FALSE) {
        inter_name *iname = Hierarchy::make_iname_in(ACTIVITY_VARC_FN_HL, pack);
        RTSharedVariables::compile_creator_fn(av->activity_variables, iname);
        Hierarchy::apply_metadata_from_iname(pack, ACTIVITY_VAR_CREATOR_MD_HL, iname);
    }
    Emit::numeric_constant(av->compilation_data.variables_id, 0);

    activity_crossref *acr;
    for (acr = av->compilation_data.cross_references; acr; acr = acr->next) {
        id_body *idb = acr->rule_dependent;
        if ((ImperativeDefinitions::body_at(idb)) &&
            (Wordings::nonempty(Node::get_text(ImperativeDefinitions::body_at(idb))))) {
            package_request *EP =
                Hierarchy::package_within(ACTIVITY_XREFS_HAP, pack);
            Hierarchy::apply_metadata_from_raw_wording(EP, XREF_TEXT_MD_HL,
                Node::get_text(ImperativeDefinitions::body_at(idb)));
            Hierarchy::apply_metadata_from_number(EP, XREF_AT_MD_HL,
                (inter_ti) Wordings::first_wn(Node::get_text(ImperativeDefinitions::body_at(idb))));
        }
    }

    text_stream *marker = av->compilation_data.translated_name;
    if (Str::len(marker) > 0) Hierarchy::apply_metadata(pack, ACTIVITY_INDEX_ID_MD_HL, marker);
}