The long production line on which products of Inform are built, one step at a time.

§1. Having seen the top management of the factory, we now reach the factory floor, which is one long production line: over 100 steps must be performed in sequence to finish making the product. We can picture each of these steps as carried out by a worker function: each does its work and passes on to the next.

We group the steps into departments, which are in order of when they work: 

enum SUBDIVIDING_CSEQ from 0
enum BUILT_IN_STUFF_CSEQ
enum SEMANTIC_ANALYSIS_CSEQ
enum ASSERTIONS_PASS_1_CSEQ
enum ASSERTIONS_PASS_2_CSEQ
enum MODEL_CSEQ
enum MODEL_COMPLETE_CSEQ
enum TABLES_CSEQ
enum AUGMENT_CSEQ
enum PHRASES_CSEQ
enum INTER1_CSEQ
enum INTER2_CSEQ
enum INTER3_CSEQ
enum INTER4_CSEQ
enum INTER5_CSEQ
enum BIBLIOGRAPHIC_CSEQ
enum FINISHED_CSEQ

§2. The aim of this section is to contain as little logic as possible other then the sequence itself. 

int Sequence::carry_out(int debugging) {
    stopwatch_timer *sequence_timer =
        Time::start_stopwatch(inform7_timer, I"compilation to Inter");
    Divide into compilation units2.2;
    Build a rudimentary set of kinds, relations, verbs and inference subjects2.3;
    Pass three times through the major nodes2.4;
    Make the model world2.5;
    Tables and grammar2.6;
    Augment model world with low-level properties2.7;
    Phrases and rules2.8;
    Generate inter, part 12.9
    Generate inter, part 22.10
    Generate inter, part 32.11
    Generate inter, part 42.12
    Generate inter, part 52.13
    Generate index and bibliographic file2.14;

    Task::advance_stage_to(FINISHED_CSEQ, I"Ccmplete", -1, debugging, sequence_timer);
    int cpu_time_used = Time::stop_stopwatch(sequence_timer);
    LOG("Compile CPU time: %d centiseconds\n", cpu_time_used);
    if (problem_count > 0) return FALSE;
    return TRUE;
}

§2.1. This macro carries out a step at what we think of as "benches" in the production line: hence the name BENCH. Continuing the analogy, there is an ongoing time and motion study: any step which takes more than 1 centisecond of CPU time is reported to the debugging log. That isn't necessarily a sign of something wrong: a few of these steps are always going to take serious computation. But we want to know which ones.

As soon as any step generates problem messages, all subsequent steps are skipped, so that each of the worker functions can assume that the part-assembled state they receive is correct so far. This greatly simplifies error recovery, prevents small errors in the source text leading to cascades of problem messages, and ensures that we report problems as quickly as possible. 

define BENCH(routine) {
    if (problem_count == 0) {
        TEMPORARY_TEXT(name)
        WRITE_TO(name, "//");
        WRITE_TO(name, #routine);
        WRITE_TO(name, "//");
        for (int i=0; i<Str::len(name)-1; i++)
            if ((Str::get_at(name, i) == '_') && (Str::get_at(name, i+1) == '_')) {
                Str::put_at(name, i, ':'); Str::put_at(name, i+1, ':');
            }
        stopwatch_timer *st = Time::start_stopwatch(sequence_timer, name);
        DISCARD_TEXT(name)
        routine();
        int cs = Time::stop_stopwatch(st);
        if (cs > 0) LOG(".... " #routine "() took %dcs\n", cs);
    }
}

§2.2. Here, then, are the steps in the production line, presented without commentary. For what they do, see the relevant sections. Note that at the end of each stage, plugins are allowed to add further steps; see Task::advance_stage_to.

Before anything else can be done, we must create an empty Inter hierarchy into which we will "emit" an Inter program. No actual code will be emitted for some time yet, but identifier names and type declarations need somewhere to go. We then break the source into "compilation units" — basically, one for the main source text and one for each extension — because the Inter hierarchy will divide according to these units.

Divide into compilation units2.2 = 

    Task::advance_stage_to(SUBDIVIDING_CSEQ, I"Dividing source into compilation units",
        -1, debugging, sequence_timer);
    BENCH(CompilationSettings::initialise_gcs)
    BENCH(Emit::begin);
    BENCH(NameResolution::make_the_tree)
    BENCH(IndexHeadings::write_as_xml)
    BENCH(CompilationUnits::determine)

§2.3. Most of the conceptual infrastructure in Inform is created by Inform source text in the Basic Inform or Standard Rules extensions, but not basic kinds of value such as "number", or the verb "to mean", or the meaning relation, and so on. Those absolute basics are made here.

Build a rudimentary set of kinds, relations, verbs and inference subjects2.3 = 

    Task::advance_stage_to(BUILT_IN_STUFF_CSEQ, I"Making built in infrastructure",
        -1, debugging, sequence_timer);
    BENCH(InferenceSubjects::make_built_in);
    BENCH(Task::make_built_in_kind_constructors);
    BENCH(BinaryPredicateFamilies::first_stock)
    BENCH(BootVerbs::make_built_in)

§2.4. Pass three times through the major nodes2.4 = 

    Task::advance_stage_to(SEMANTIC_ANALYSIS_CSEQ, I"Pre-pass through major nodes",
        1, debugging, sequence_timer);
    BENCH(MajorNodes::pre_pass)
    BENCH(Task::verify)
    Task::advance_stage_to(ASSERTIONS_PASS_1_CSEQ, I"First pass through major nodes",
        2, debugging, sequence_timer);
    BENCH(MajorNodes::pass_1)
    BENCH(Tables::traverse_to_stock)
    Task::advance_stage_to(ASSERTIONS_PASS_2_CSEQ, I"Second pass through major nodes",
        -1, debugging, sequence_timer);
    BENCH(MajorNodes::pass_2)

§2.5. Make the model world2.5 = 

    Task::advance_stage_to(MODEL_CSEQ, I"Making the model world",
        -1, debugging, sequence_timer);
    BENCH(RTKinds::kind_declarations)
    BENCH(RTUseOptions::compile)
    BENCH(RTProperties::emit)
    BENCH(RTPropertyValues::allocate_attributes)
    BENCH(NounIdentifiers::name_all)
    BENCH(OrderingInstances::objects_in_definition_sequence)
    Task::advance_stage_to(MODEL_COMPLETE_CSEQ, I"Completing the model world",
        -1, debugging, sequence_timer);
    BENCH(World::stages_II_and_III)
    BENCH(World::stage_IV)

§2.6. Tables and grammar2.6 = 

    Task::advance_stage_to(TABLES_CSEQ, I"Tables and grammar",
        -1, debugging, sequence_timer);
    BENCH(Measurements::validate_definitions)
    BENCH(BinaryPredicateFamilies::second_stock)
    BENCH(Tables::check_tables_for_kind_clashes)
    BENCH(RTTables::compile_print_table_names)

§2.7. Augment model world with low-level properties2.7 = 

    Task::advance_stage_to(AUGMENT_CSEQ, I"Augment model world",
        -1, debugging, sequence_timer);
    BENCH(World::stage_V)

§2.8. Phrases and rules2.8 = 

    Task::advance_stage_to(PHRASES_CSEQ, I"Phrases and rules",
        3, debugging, sequence_timer);
    BENCH(LiteralPatterns::define_named_phrases)
    BENCH(Phrases::Manager::traverse)
    BENCH(Phrases::Manager::register_meanings)
    BENCH(Phrases::Manager::parse_rule_parameters)
    BENCH(Phrases::Manager::add_rules_to_rulebooks)
    BENCH(Phrases::Manager::parse_rule_placements)
    BENCH(Equations::traverse_to_stock)
    BENCH(Tables::traverse_to_stock)
    BENCH(RTProperties::annotate_attributes)
    BENCH(Rulebooks::Outcomes::RulebookOutcomePrintingRule)
    BENCH(RTKinds::compile_instance_counts)

§2.9. This proceeds in stages.

Generate inter, part 12.9 = 

    Task::advance_stage_to(INTER1_CSEQ, I"Generating inter (1)",
        4, debugging, sequence_timer);
    BENCH(RTUseOptions::compile_pragmas)
    BENCH(FundamentalConstants::emit_build_number)
    BENCH(RTExtensions::ShowExtensionVersions_routine)
    BENCH(Kinds::Constructors::emit_constants)
    BENCH(RTUseOptions::TestUseOption_routine)
    BENCH(Activities::compile_activity_constants)
    BENCH(Activities::Activity_before_rulebooks_array)
    BENCH(Activities::Activity_for_rulebooks_array)
    BENCH(Activities::Activity_after_rulebooks_array)
    BENCH(Activities::Activity_atb_rulebooks_array)
    BENCH(RTRelations::compile_defined_relation_constants)
    BENCH(RTKinds::compile_data_type_support_routines)
    BENCH(RTKinds::I7_Kind_Name_routine)

§2.10. Generate inter, part 22.10 = 

    Task::advance_stage_to(INTER2_CSEQ, I"Generating inter (2)",
        -1, debugging, sequence_timer);
    BENCH(InferenceSubjects::emit_all)
    BENCH(Tables::complete)
    BENCH(RTTables::compile)
    BENCH(RTEquations::compile_identifiers)
    BENCH(Phrases::Manager::compile_first_block)
    BENCH(Phrases::Manager::compile_rulebooks)
    BENCH(Phrases::Manager::rulebooks_array)
    BENCH(Rulebooks::rulebook_var_creators)
    BENCH(Activities::activity_var_creators)
    BENCH(RTRelations::IterateRelations)
    BENCH(Phrases::Manager::RulebookNames_array)
    BENCH(Phrases::Manager::RulePrintingRule_routine)
    BENCH(RTVerbs::ConjugateVerb)
    BENCH(RTAdjectives::agreements)
    if (debugging) {
        BENCH(InternalTests::InternalTestCases_routine)
    }

§2.11. Generate inter, part 32.11 = 

    Task::advance_stage_to(INTER3_CSEQ, I"Generating inter (3)",
        -1, debugging, sequence_timer);
    BENCH(Lists::check)
    BENCH(ConstantLists::compile)
    BENCH(Phrases::invoke_to_begin)
    BENCH(Phrases::Manager::compile_as_needed)
    BENCH(Strings::compile_responses)
    BENCH(Lists::check)
    BENCH(ConstantLists::compile)
    BENCH(RTRelations::compile_defined_relations)
    BENCH(Phrases::Manager::compile_as_needed)
    BENCH(Strings::TextSubstitutions::allow_no_further_text_subs)

§2.12. Generate inter, part 42.12 = 

    Task::advance_stage_to(INTER4_CSEQ, I"Generating inter (4)",
        -1, debugging, sequence_timer);
    BENCH(Chronology::past_actions_i6_routines)
    BENCH(Chronology::compile_runtime)

§2.13. Generate inter, part 52.13 = 

    Task::advance_stage_to(INTER5_CSEQ, I"Generating inter (5)",
        -1, debugging, sequence_timer);
    BENCH(RTMeasurements::compile_test_functions)
    BENCH(Propositions::Deferred::compile_remaining_deferred)
    BENCH(Calculus::Deferrals::allow_no_further_deferrals)
    BENCH(Lists::check)
    BENCH(ConstantLists::compile)
    BENCH(TextLiterals::compile)
    BENCH(JumpLabels::compile_necessary_storage)
    BENCH(RTKinds::compile_heap_allocator)
    BENCH(Phrases::Constants::compile_closures)
    BENCH(RTKinds::compile_structures)
    BENCH(Rules::check_response_usages)
    BENCH(Phrases::Timed::check_for_unused)
    BENCH(Phrases::Timed::TimedEventsTable)
    BENCH(Phrases::Timed::TimedEventTimesTable)
    BENCH(RTUseOptions::configure_template)
    BENCH(RTBibliographicData::IFID_text);

§2.14. Generate index and bibliographic file2.14 = 

    Task::advance_stage_to(BIBLIOGRAPHIC_CSEQ, I"Bibliographic work",
        -1, debugging, sequence_timer);
    BENCH(I6T::produce_index);