Defining the propertyvalue construct.

§1. 

enum PROPERTYVALUE_IST

void Inter::PropertyValue::define(void) {
    inter_construct *IC = Inter::Defn::create_construct(
        PROPERTYVALUE_IST,
        L"propertyvalue (%i+) (%i+) = (%c+)",
        I"propertyvalue", I"propertyvalues");
    METHOD_ADD(IC, CONSTRUCT_READ_MTID, Inter::PropertyValue::read);
    METHOD_ADD(IC, CONSTRUCT_VERIFY_MTID, Inter::PropertyValue::verify);
    METHOD_ADD(IC, CONSTRUCT_WRITE_MTID, Inter::PropertyValue::write);
}

§2. 

define PROP_PVAL_IFLD 2
define OWNER_PVAL_IFLD 3
define DVAL1_PVAL_IFLD 4
define DVAL2_PVAL_IFLD 5
define EXTENT_PVAL_IFR 6

void Inter::PropertyValue::read(inter_construct *IC, inter_bookmark *IBM, inter_line_parse *ilp, inter_error_location *eloc, inter_error_message **E) {
    *E = Inter::Defn::vet_level(IBM, PROPERTYVALUE_IST, ilp->indent_level, eloc);
    if (*E) return;

    if (Inter::Annotations::exist(&(ilp->set))) { *E = Inter::Errors::plain(I"__annotations are not allowed", eloc); return; }

    inter_symbol *prop_name = Inter::Textual::find_symbol(Inter::Bookmarks::tree(IBM), eloc, Inter::Bookmarks::scope(IBM), ilp->mr.exp[0], PROPERTY_IST, E);
    if (*E) return;
    inter_symbol *owner_name = Inter::Textual::find_KOI(eloc, Inter::Bookmarks::scope(IBM), ilp->mr.exp[1], E);
    if (*E) return;

    inter_ti plist_ID;
    if (Inter::Kind::is(owner_name)) plist_ID = Inter::Kind::properties_list(owner_name);
    else plist_ID = Inter::Instance::properties_list(owner_name);
    inter_node_list *FL = Inter::Warehouse::get_frame_list(Inter::Bookmarks::warehouse(IBM), plist_ID);
    if (FL == NULL) internal_error("no properties list");

    inter_tree_node *X;
    LOOP_THROUGH_INTER_NODE_LIST(X, FL) {
        inter_symbol *prop_X = InterSymbolsTables::symbol_from_frame_data(X, PROP_PVAL_IFLD);
        if (prop_X == prop_name)
            { *E = Inter::Errors::quoted(I"property already given", ilp->mr.exp[0], eloc); return; }
    }

    inter_symbol *val_kind = Inter::Property::kind_of(prop_name);
    inter_ti con_val1 = 0;
    inter_ti con_val2 = 0;
    *E = Inter::Types::read(ilp->line, eloc, Inter::Bookmarks::tree(IBM), Inter::Bookmarks::package(IBM), val_kind, ilp->mr.exp[2], &con_val1, &con_val2, Inter::Bookmarks::scope(IBM));
    if (*E) return;

    *E = Inter::PropertyValue::new(IBM, InterSymbolsTables::id_from_IRS_and_symbol(IBM, prop_name), InterSymbolsTables::id_from_IRS_and_symbol(IBM, owner_name),
        con_val1, con_val2, (inter_ti) ilp->indent_level, eloc);
}

int Inter::PropertyValue::permitted(inter_tree_node *F, inter_package *pack, inter_symbol *owner, inter_symbol *prop_name) {
    inter_ti plist_ID;
    if (Inter::Kind::is(owner)) plist_ID = Inter::Kind::permissions_list(owner);
    else plist_ID = Inter::Instance::permissions_list(owner);
    inter_node_list *FL = Inode::ID_to_frame_list(F, plist_ID);
    inter_tree_node *X;
    LOOP_THROUGH_INTER_NODE_LIST(X, FL) {
        inter_symbol *prop_allowed = InterSymbolsTables::symbol_from_frame_data(X, PROP_PERM_IFLD);
        if (prop_allowed == prop_name)
            return TRUE;
    }
    inter_symbol *inst_kind;
    if (Inter::Kind::is(owner)) inst_kind = Inter::Kind::super(owner);
    else inst_kind = Inter::Instance::kind_of(owner);
    while (inst_kind) {
        inter_node_list *FL =
            Inode::ID_to_frame_list(F, Inter::Kind::permissions_list(inst_kind));
        if (FL == NULL) internal_error("no permissions list");
        inter_tree_node *X;
        LOOP_THROUGH_INTER_NODE_LIST(X, FL) {
            inter_symbol *prop_allowed = InterSymbolsTables::symbol_from_frame_data(X, PROP_PERM_IFLD);
            if (prop_allowed == prop_name)
                return TRUE;
        }
        inst_kind = Inter::Kind::super(inst_kind);
    }
    return FALSE;
}

inter_error_message *Inter::PropertyValue::new(inter_bookmark *IBM, inter_ti PID, inter_ti OID,
    inter_ti con_val1, inter_ti con_val2, inter_ti level, inter_error_location *eloc) {
    inter_tree_node *P = Inode::fill_4(IBM, PROPERTYVALUE_IST,
        PID, OID, con_val1, con_val2, eloc, level);
    inter_error_message *E = Inter::Defn::verify_construct(Inter::Bookmarks::package(IBM), P); if (E) return E;
    Inter::Bookmarks::insert(IBM, P);
    return NULL;
}

void Inter::PropertyValue::verify(inter_construct *IC, inter_tree_node *P, inter_package *owner, inter_error_message **E) {
    inter_ti vcount = Inode::vcount(P);

    if (P->W.extent != EXTENT_PVAL_IFR) { *E = Inode::error(P, I"extent wrong", NULL); return; }
    *E = Inter::Verify::symbol(owner, P, P->W.data[PROP_PVAL_IFLD], PROPERTY_IST); if (*E) return;
    *E = Inter::Verify::symbol_KOI(owner, P, P->W.data[OWNER_PVAL_IFLD]); if (*E) return;

    if (vcount == 0) {
        inter_symbol *prop_name = InterSymbolsTables::symbol_from_id(Inter::Packages::scope(owner), P->W.data[PROP_PVAL_IFLD]);;
        inter_symbol *owner_name = InterSymbolsTables::symbol_from_id(Inter::Packages::scope(owner), P->W.data[OWNER_PVAL_IFLD]);;

        if (Inter::PropertyValue::permitted(P, owner, owner_name, prop_name) == FALSE) {
            text_stream *err = Str::new();
            WRITE_TO(err, "no permission for '%S' have this property", owner_name->symbol_name);
            *E = Inode::error(P, err, prop_name->symbol_name); return;
        }

        inter_ti plist_ID;
        if (Inter::Kind::is(owner_name)) plist_ID = Inter::Kind::properties_list(owner_name);
        else plist_ID = Inter::Instance::properties_list(owner_name);

        inter_node_list *FL = Inode::ID_to_frame_list(P, plist_ID);
        if (FL == NULL) internal_error("no properties list");

        inter_tree_node *X;
        LOOP_THROUGH_INTER_NODE_LIST(X, FL) {
            if (X->W.data[PROP_PVAL_IFLD] == P->W.data[PROP_PVAL_IFLD]) { *E = Inode::error(P, I"duplicate property value", NULL); return; }
            if (X->W.data[OWNER_PVAL_IFLD] != P->W.data[OWNER_PVAL_IFLD]) { *E = Inode::error(P, I"instance property list malformed", NULL); return; }
        }

        Inter::ListLiterals::add(FL, P);
    }
}

void Inter::PropertyValue::write(inter_construct *IC, OUTPUT_STREAM, inter_tree_node *P, inter_error_message **E) {
    inter_symbol *prop_name = InterSymbolsTables::symbol_from_frame_data(P, PROP_PVAL_IFLD);
    inter_symbol *owner_name = InterSymbolsTables::symbol_from_frame_data(P, OWNER_PVAL_IFLD);
    if ((prop_name) && (owner_name)) {
        inter_symbol *val_kind = Inter::Property::kind_of(InterSymbolsTables::symbol_from_frame_data(P, PROP_PVAL_IFLD));
        WRITE("propertyvalue %S %S = ", prop_name->symbol_name, owner_name->symbol_name);
        Inter::Types::write(OUT, P, val_kind, P->W.data[DVAL1_PVAL_IFLD], P->W.data[DVAL2_PVAL_IFLD], Inter::Packages::scope_of(P), FALSE);
    } else { *E = Inode::error(P, I"cannot write propertyvalue", NULL); return; }
}