A pipeline stage for generating the index of an Inform project.

§1. This is not really a general-purpose pipeline stage: it makes sense only in the context of an Inform compilation run, and will (silently) do nothing if run in any other pipeline.

void IndexStage::create_pipeline_stage(void) {
    ParsingPipelines::new_stage(I"index", IndexStage::run,
        NO_STAGE_ARG, FALSE);
}

§2. The implementation here needs an inform_project structure to work from, and that exists only in the supervisor module — which is not a part of the Inter stand-alone tool. So running inter at the command line does not allow the indexer to do anything.

Moreover, and in a sneaky fashion, updating the extensions documentation and generating an EPS map are also sometimes part of the indexing process, depending on the command-line settings used when invoking inform7.

define INDEX_REQUIRED_BIT 1
define EXTENSIONS_INDEX_REQUIRED_BIT 2
define EPS_MAP_REQUIRED_BIT 4

int IndexStage::run?Usage of IndexStage::run:
§1(pipeline_step *step) {
    #ifdef SUPERVISOR_MODULE
    inter_tree *I = step->ephemera.tree;
    int req = INDEX_REQUIRED_BIT;
    #ifdef CORE_MODULE
    req = Task::get_index_requirements();
    #endif
    inform_project *project = InterSkill::get_associated_project();
    if (project) {
        if ((req & INDEX_REQUIRED_BIT) ||
            (req & EPS_MAP_REQUIRED_BIT) ||
            (req & EXTENSIONS_INDEX_REQUIRED_BIT)) {
            index_session *session = IndexStage::index_session_for(I, project);
            if (req & INDEX_REQUIRED_BIT)
                Indexing::generate_index_website(session, Projects::index_structure(project));
            if (req & EXTENSIONS_INDEX_REQUIRED_BIT)
                ExtensionWebsite::update(project);
            #ifdef CORE_MODULE
            if (req & EPS_MAP_REQUIRED_BIT)
                Indexing::generate_EPS_map(session, Task::epsmap_file(), NULL);
            #endif
            Indexing::close_session(session);
        }
    }
    #endif
    return TRUE;
}

§3. The actual indexing work is all done using the Indexing API.

#ifdef SUPERVISOR_MODULE
index_session *IndexStage::index_session_for?Usage of IndexStage::index_session_for:
§2(inter_tree *I, inform_project *project) {
    index_session *session = Indexing::open_session(I);
    inform_language *E = Languages::find_for(I"English", Projects::nest_list(project));
    inform_language *L = Projects::get_language_of_index(project);
    if (E != L)
        Indexing::localise(session,
            Filenames::in(Languages::path_to_bundle(E), I"Index.txt"));
    Indexing::localise(session,
        Filenames::in(Languages::path_to_bundle(L), I"Index.txt"));
    return session;
}
#endif