Claro Now Fully Supports Modules Exporting Static Values Initialized …

…on Program Startup!

This is a massive development as it eliminates a large portion of the use cases that dependency injection frameworks get used for! Now, a module can simply declare that it statically exports a static value, and the entire program can use this singleton, deeply-immutable, non-reassignable value anywhere in the program. As a strong argument for the power of this functionality, I've included an update of the Buggy Buggies demo server that takes advantage of this new functionality to allow the use of a *single* statically initialized `HttpClient<BuggyBuggies>` instance throughout the entire server lifetime, whereas prior to this it was impossible for a Claro Server to maintain any state whatsoever, so clients had to be continuously re-initialized on the fly.

To take this example even further, to demonstrate how Claro's static values can eliminate the need for any dependency injection framework, I could use Bazel to select a static value provider at build time based on some flag like `--dev` or `--prod`. See: https://bazel.build/docs/configurable-attributes.

WORKSPACE

@@ -49,8 +49,8 @@ http_file(
     # In some way, it'd be nicer to make use of https://github.com/JasonSteving99/claro-lang/releases/latest/download/..
     # instead of naming the release explicitly. However, this would make it impossible to cherrypick an old version and
     # rebuild without manual work.
-    sha256 = "316f6a8399f5b9f5296458b3c9759330fe9b692dac90833a78f709329251db0e",
-    url = "https://github.com/JasonSteving99/claro-lang/releases/download/v0.1.277/claro-cli-install.tar.gz",
+    sha256 = "0d4a4eb0083f3b89b9ecfb740acbce3c1addfa5f3233e6693ec66db487f5942d",
+    url = "https://github.com/JasonSteving99/claro-lang/releases/download/v0.1.278/claro-cli-install.tar.gz",
 )
 
 # ClaroDocs is built atop Google's Closure Templates in order to ensure that I'm not generating unsafe html since the

src/java/com/claro/claro_programs/demo_server/buggy_buggies/buggy_buggies_http_server.claro

@@ -32,8 +32,7 @@ endpoint_handlers MyDemoService {
     root res <- http::getOk200HttpResponseForHtml(@formattedHtml);
     node formattedHtml <- Utils::handleBuggyResponseAsHtmlStrParts(@joinResponse)[0];
     node joinResponse <- BuggyBuggies::friendsJoin(
-      # TODO(steving) Migrate to using a singleton client once Claro's Modules can export static (singleton) values.
-      BuggyBuggies::getClient("https://buggy-buggies.gigalixirapp.com"),
+      BuggyBuggies::HTTP_CLIENT,
       gameId,
       handle
     );
@@ -49,8 +48,7 @@ endpoint_handlers MyDemoService {
     root res <- http::getOk200HttpResponseForJson(@formattedJson);
     node formattedJson <- EndpointHandlers::getBestMovesHandler(@parsedWorld);
     node parsedWorld <- BuggyBuggies::worldInfo(
-      # TODO(steving) Migrate to using a singleton client once Claro's Modules can export static (singleton) values.
-      BuggyBuggies::getClient("https://buggy-buggies.gigalixirapp.com"),
+      BuggyBuggies::HTTP_CLIENT,
       gameId,
       playerSecret
     );
@@ -60,8 +58,7 @@ endpoint_handlers MyDemoService {
     root res <- http::getOk200HttpResponseForJson(@formattedJson);
     node formattedJson <- Utils::handleBuggyResponseAsHtmlStrParts(@resetResponse)[0];
     node resetResponse <- BuggyBuggies::reset(
-      # TODO(steving) Migrate to using a singleton client once Claro's Modules can export static (singleton) values.
-      BuggyBuggies::getClient("https://buggy-buggies.gigalixirapp.com"),
+      BuggyBuggies::HTTP_CLIENT,
       gameId,
       playerSecret
     );

src/java/com/claro/claro_programs/demo_server/buggy_buggies/buggy_buggies_service/buggy_buggies_client.claro

@@ -1,4 +1,5 @@
 
-function getClient(url: string) -> HttpClient<BuggyBuggies> {
-  return http::getHttpClient(url);
+provider static_HTTP_CLIENT() -> HttpClient<BuggyBuggies> {
+  # This now only needs to happen once throughout the entire program.
+  return http::getHttpClient("https://buggy-buggies.gigalixirapp.com");
 }

src/java/com/claro/claro_programs/demo_server/buggy_buggies/buggy_buggies_service/buggy_buggies_client.claro_module_api

@@ -10,7 +10,8 @@ HttpService BuggyBuggies {
   reset: "/api/game/{gameId}/player/{secret}/reset"
 }
 
-function getClient(url: string) -> HttpClient<BuggyBuggies>;
+# Now there's a single static definition of which client will be used for sending reqs to the Buggy Buggies server.
+static HTTP_CLIENT: HttpClient<BuggyBuggies>;
 
 # This type models the JSON response from the Buggy-Buggies service as a Claro type to enable parsing the response into
 # something that you can work with programmatically with strict type validation on the edge.

src/java/com/claro/claro_programs/demo_server/buggy_buggies/endpoint_handlers/BUILD

@@ -13,7 +13,7 @@ claro_module(
     ],
     deps = {
         "Agent": "//src/java/com/claro/claro_programs/demo_server/buggy_buggies/buggy_agent:buggy_agent",
-        "BuggyBuggiesClient": "//src/java/com/claro/claro_programs/demo_server/buggy_buggies/buggy_buggies_service:buggy_buggies_client",
+        "BuggyBuggies": "//src/java/com/claro/claro_programs/demo_server/buggy_buggies/buggy_buggies_service:buggy_buggies_client",
         "Utils": "//src/java/com/claro/claro_programs/demo_server/buggy_buggies/utils:utils",
         "Pos": "//src/java/com/claro/claro_programs/demo_server/buggy_buggies/data_structures:position",
     },

src/java/com/claro/claro_programs/demo_server/buggy_buggies/endpoint_handlers/game_move_handler.claro

@@ -3,9 +3,8 @@ graph function gameMoveHandler(gameId: string, playerSecret: string, dir: string
   root formattedHtml <- Utils::reduce(@htmlStrParts, "", lambda (accum, curr) -> { return "{accum}{curr}"; });
   node htmlStrParts <- Utils::handleBuggyResponseAsHtmlStrParts(@moveBuggyResponse);
   node moveBuggyResponse <-
-    BuggyBuggiesClient::move(
-      # TODO(steving) Migrate to using a singleton client once Claro's Modules can export static (singleton) values.
-      BuggyBuggiesClient::getClient("https://buggy-buggies.gigalixirapp.com"),
+    BuggyBuggies::move(
+      BuggyBuggies::HTTP_CLIENT,
       gameId,
       playerSecret,
       dir

src/java/com/claro/claro_programs/demo_server/buggy_buggies/endpoint_handlers/get_best_moves_handler.claro

@@ -2,9 +2,9 @@
 function getBestMovesHandler(buggyResponse: oneof<string, std::Error<string>>) -> string {
   match (buggyResponse) {
     case _:string ->
-      var moveResponse = unwrap(BuggyBuggiesClient::getParsedMoveResponse(buggyResponse)).result;
+      var moveResponse = unwrap(BuggyBuggies::getParsedMoveResponse(buggyResponse)).result;
       match (moveResponse) {
-        case _:BuggyBuggiesClient::MoveResponse ->
+        case _:BuggyBuggies::MoveResponse ->
           Agent::parseWorldMap(moveResponse.result.world)
           |> Agent::dijkstra(^, Pos::Position({x = moveResponse.result.you.x, y = moveResponse.result.you.y}))
           |> var computedMoves = ["\"{dir}\"" | dir in Agent::movesFromBestPath(^)];

src/java/com/claro/claro_programs/demo_server/buggy_buggies/endpoint_handlers/start_new_game_handler.claro

@@ -1,10 +1,5 @@
 
 graph function startNewGameHandler(handle: string) -> future<string> {
   root joinRes <- Utils::handleBuggyResponseAsHtmlStrParts(@moveBuggyResponse)[0];
-  node moveBuggyResponse <-
-    BuggyBuggiesClient::hostGame(
-      # TODO(steving) Migrate to using a singleton client once Claro's Modules can export static (singleton) values.
-      BuggyBuggiesClient::getClient("https://buggy-buggies.gigalixirapp.com"),
-      handle
-    );
+  node moveBuggyResponse <- BuggyBuggies::hostGame(BuggyBuggies::HTTP_CLIENT, handle);
 }

src/java/com/claro/claro_programs/modules/test_main.claro

@@ -27,4 +27,7 @@ TestDep2::addFancyInt(2, 3)
 |> myPrint(^, ":multi_hop_module_api via Addition via TestDep2");
 
 # Demonstrate that dep module types with generic type params can actually be instantiated.
-print(TestDep2::List([1]));
+print(TestDep2::List([1]));
+
+# Demonstrate that static values exported by dep modules can be read.
+print("Here's the definition of `TestDep::PI`: {TestDep::PI}");

src/java/com/claro/compiler_backends/java_source/JavaSourceCompilerBackend.java

@@ -431,8 +431,27 @@ private ImmutableList<ContractDefinitionStmt> setupModuleDepBindings(
     }
 
     // After having successfully parsed all dep module files and registered all of their exported types, it's time to
-    // finally register all of their exported procedure signatures.
+    // finally register their remaining exports.
     ImmutableMap<String, SerializedClaroModule> parsedClaroModuleProtos = parsedClaroModuleProtosBuilder.build();
+
+    // Register the exported static values.
+    for (Map.Entry<String, SerializedClaroModule> moduleDep : parsedClaroModuleProtos.entrySet()) {
+      // Setup the regular exported procedures.
+      for (SerializedClaroModule.ExportedStaticValue depExportedStaticValue :
+          moduleDep.getValue().getExportedStaticValuesList()) {
+        String disambiguatedStaticValueIdentifier =
+            String.format(
+                "%s$%s",
+                depExportedStaticValue.getName(),
+                moduleDep.getValue().getModuleDescriptor().getUniqueModuleName()
+            );
+        scopedHeap.observeStaticIdentifierValue(
+            disambiguatedStaticValueIdentifier, Types.parseTypeProto(depExportedStaticValue.getType()));
+        scopedHeap.initializeIdentifier(disambiguatedStaticValueIdentifier);
+      }
+    }
+
+    // Register the exported procedures.
     for (Map.Entry<String, SerializedClaroModule> moduleDep : parsedClaroModuleProtos.entrySet()) {
       // Setup the regular exported procedures.
       for (SerializedClaroModule.Procedure depExportedProc :

src/java/com/claro/intermediate_representation/expressions/term/IdentifierReferenceTerm.java

@@ -8,7 +8,6 @@
 import com.claro.intermediate_representation.types.Type;
 import com.claro.intermediate_representation.types.Types;
 import com.claro.internal_static_state.InternalStaticStateUtil;
-import com.claro.module_system.module_serialization.proto.SerializedClaroModule;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
@@ -221,31 +220,20 @@ public Type getValidatedExprType(ScopedHeap scopedHeap) throws ClaroTypeExceptio
 
   @Override
   public StringBuilder generateJavaSourceBodyOutput(ScopedHeap scopedHeap) {
-    scopedHeap.markIdentifierUsed(this.identifier);
+    if (scopedHeap.getIdentifierData(this.identifier).isStaticValue) {
+      System.err.println(
+          "TESTING!!! FOUND STATIC ID REF: " + this.identifier + " " + this.optionalDefiningModuleDisambiguator);
+    }
+    ScopedHeap.IdentifierData identifierData = scopedHeap.getIdentifierData(this.identifier);
+    identifierData.used = true;
     return new StringBuilder(
         this.alternateCodegenString.orElse(
             () -> {
-              if (scopedHeap.getValidatedIdentifierType(this.identifier).baseType().equals(BaseType.ATOM)
-                  && scopedHeap.getIdentifierData(this.identifier).isTypeDefinition) {
+              if (identifierData.type.baseType().equals(BaseType.ATOM) && identifierData.isTypeDefinition) {
                 // Here it turns out that we actually need to codegen a lookup into the ATOM CACHE.
-                Optional<SerializedClaroModule.UniqueModuleDescriptor> uniqueModuleDescriptor =
-                    ScopedHeap.getModuleNameFromDisambiguator(
-                            this.optionalDefiningModuleDisambiguator.orElse("$THIS_MODULE$"))
-                        .map(moduleName ->
-                                 ScopedHeap.currProgramDepModules.rowMap().get(moduleName)
-                                     .values().stream().findFirst().get());
                 return String.format(
-                    "%s%sATOM_CACHE[%s]",
-                    uniqueModuleDescriptor.map(m -> m.getProjectPackage() + '.').orElse(""),
-                    this.optionalDefiningModuleDisambiguator.map(s -> s + '.').orElseGet(
-                        () -> {
-                          String definingModuleDisambiguator =
-                              ScopedHeap.getDefiningModuleDisambiguator(Optional.empty());
-                          if (definingModuleDisambiguator.isEmpty()) {
-                            return definingModuleDisambiguator;
-                          }
-                          return definingModuleDisambiguator + '.';
-                        }),
+                    "%sATOM_CACHE[%s]",
+                    getFullySpecifiedIdentifierNamespace(),
                     InternalStaticStateUtil.AtomDefinition_CACHE_INDEX_BY_MODULE_AND_ATOM_NAME.build().get(
                         this.optionalDefiningModuleDisambiguator.orElseGet(
                             () -> ScopedHeap.getDefiningModuleDisambiguator(Optional.empty())),
@@ -256,12 +244,38 @@ public StringBuilder generateJavaSourceBodyOutput(ScopedHeap scopedHeap) {
                 // Nested comprehension Exprs depend on a synthetic class wrapping the nested identifier refs to
                 // workaround Java's restriction that all lambda captures must be effectively final.
                 return "$nestedComprehensionState." + this.identifier;
+              } else if (identifierData.isStaticValue) {
+                // To ensure that static values can be referenced across dep module monomorphization boundaries, I need
+                // to fully specify their namespace at all times.
+                return getFullySpecifiedIdentifierNamespace() +
+                       this.optionalDefiningModuleDisambiguator
+                           .map(unused -> {
+                             int identifierEndIndex = this.identifier.indexOf('$');
+                             if (identifierEndIndex == -1) {
+                               return this.identifier;
+                             }
+                             return this.identifier.substring(0, identifierEndIndex);
+                           })
+                           .orElse(this.identifier);
               }
               return this.identifier;
             }
         ).get());
   }
 
+  // Returns empty only if referencing an identifier from the current compilation unit, and the current compilation unit
+  // is in fact the top-level claro_binary(). Else, returns the actual UniqueModuleDescriptor to explicitly reference
+  // currently identifier.
+  private String getFullySpecifiedIdentifierNamespace() {
+    return ScopedHeap.getModuleNameFromDisambiguator(
+            this.optionalDefiningModuleDisambiguator.orElse("$THIS_MODULE$"))
+        .map(moduleName ->
+                 ScopedHeap.currProgramDepModules.rowMap().get(moduleName)
+                     .values().stream().findFirst().get())
+        .map(m -> String.format("%s.%s.", m.getProjectPackage(), m.getUniqueModuleName()))
+        .orElse("");
+  }
+
   @Override
   public Object generateInterpretedOutput(ScopedHeap scopedHeap) {
     scopedHeap.markIdentifierUsed(this.identifier);