To renumber the extensions and construct suitable functions and arrays.

§1. Before this runs, there are one or more modules in the Inter tree which contain the material compiled from extensions. We must allocate each one a unique ID.

As this is called, Synoptic Utilities has already formed a list extension_nodes of packages of type _module which derive from extensions.

void SynopticExtensions::compile?Usage of SynopticExtensions::compile:
Synoptic Utilities - §1(inter_tree *I, pipeline_step *step, tree_inventory *inv) {
    if (TreeLists::len(inv->extension_nodes) > 0) {
        TreeLists::sort(inv->extension_nodes, Synoptic::category_order);
        for (int i=0; i<TreeLists::len(inv->extension_nodes); i++) {
            inter_package *pack = Inter::Package::defined_by_frame(inv->extension_nodes->list[i].node);
            inter_tree_node *D = Synoptic::get_definition(pack, I"extension_id");
            D->W.data[DATA_CONST_IFLD+1] = (inter_ti) (i + 1);
        }
    }
    Define SHOWEXTENSIONVERSIONS function1.1;
    Define SHOWFULLEXTENSIONVERSIONS function1.2;
    Define SHOWONEEXTENSION function1.3;
}

§1.1. Extensions have an obvious effect at runtime — they include extra material. But there are also just three functions which deal with extensions as if they were values; all of them simply print credits out.

This is more important than it may sound because many extensions are published under a Creative Commons attribution license which requires users to give credit to the authors: Inform thus ensures that this happens automatically.

There are two forms of exemption from this —

• ● specific authorial modesty suppresses the author's name for one extension, at that extension author's discretion;
• ● general authorial modesty suppresses the author's name for any extensions by the same person who wrote the main source text.

By design, however, the author of the main source text cannot remove the name of a different author writing an extension which did not ask for modesty. That would violate the CC license.

Define SHOWEXTENSIONVERSIONS function1.1 =

    inter_name *iname = HierarchyLocations::find(I, SHOWEXTENSIONVERSIONS_HL);
    Synoptic::begin_function(I, iname);
    for (int i=0; i<TreeLists::len(inv->extension_nodes); i++) {
        inter_package *pack = Inter::Package::defined_by_frame(inv->extension_nodes->list[i].node);
        inter_ti modesty = Metadata::read_numeric(pack, I"^modesty");
        if (modesty == 0) {
            text_stream *credit = Str::duplicate(Metadata::read_textual(pack, I"^credit"));
            WRITE_TO(credit, "\n");
            Produce::inv_primitive(I, PRINT_BIP);
            Produce::down(I);
                Produce::val_text(I, credit);
            Produce::up(I);
        }
    }
    Synoptic::end_function(I, step, iname);

• This code is used in §1.

§1.2. This fuller version does not allow the exemptions.

Define SHOWFULLEXTENSIONVERSIONS function1.2 =

    inter_name *iname = HierarchyLocations::find(I, SHOWFULLEXTENSIONVERSIONS_HL);
    Synoptic::begin_function(I, iname);
    for (int i=0; i<TreeLists::len(inv->extension_nodes); i++) {
        inter_package *pack = Inter::Package::defined_by_frame(inv->extension_nodes->list[i].node);
        text_stream *credit = Str::duplicate(Metadata::read_textual(pack, I"^credit"));
        WRITE_TO(credit, "\n");
        Produce::inv_primitive(I, PRINT_BIP);
        Produce::down(I);
            Produce::val_text(I, credit);
        Produce::up(I);
    }
    Synoptic::end_function(I, step, iname);

• This code is used in §1.

§1.3. This prints the name of a single extension, identified by a value which is its extension ID.

Define SHOWONEEXTENSION function1.3 =

    inter_name *iname = HierarchyLocations::find(I, SHOWONEEXTENSION_HL);
    Synoptic::begin_function(I, iname);
    inter_symbol *id_s = Synoptic::local(I, I"id", NULL);
    for (int i=0; i<TreeLists::len(inv->extension_nodes); i++) {
        inter_package *pack = Inter::Package::defined_by_frame(inv->extension_nodes->list[i].node);
        text_stream *credit = Metadata::read_textual(pack, I"^credit");
        Produce::inv_primitive(I, IF_BIP);
        Produce::down(I);
            Produce::inv_primitive(I, EQ_BIP);
            Produce::down(I);
                Produce::val_symbol(I, K_value, id_s);
                Produce::val(I, K_value, LITERAL_IVAL, (inter_ti) (i + 1));
            Produce::up(I);
            Produce::code(I);
            Produce::down(I);
                Produce::inv_primitive(I, PRINT_BIP);
                Produce::down(I);
                    Produce::val_text(I, credit);
                Produce::up(I);
            Produce::up(I);
        Produce::up(I);
    }
    Synoptic::end_function(I, step, iname);

• This code is used in §1.