symbols in build.lab no longer cause conflicts, support for faster symbol resolution and declaration by caching, user can also import selected symbols instead of all

Author: wakaztahir

compiler/ASTProcessor.cpp

@@ -394,18 +394,6 @@ int ASTProcessor::sym_res_module(LabModule* module) {
 int ASTProcessor::sym_res_module_seq(LabModule* module) {
     const auto mod_index = resolver->module_scope_start();
 
-    // declare symbols of directly imported modules
-
-    SymbolResolverShadowDeclarer declarer(*resolver);
-    for(const auto dep : module->dependencies) {
-        for(auto& file_ptr : dep->direct_files) {
-            auto& file = *file_ptr.result;
-            for(const auto node : file.unit.scope.body.nodes) {
-                declare_node(declarer, node, AccessSpecifier::Public);
-            }
-        }
-    }
-
     // declare symbols for all files once in the module
 
     for(auto& file_ptr : module->direct_files) {

compiler/symres/DeclareTopLevel.cpp

@@ -63,7 +63,15 @@ static void append_alias_and_part(Diag& d, const std::vector<chem::string_view>&
 void declareChildren(SymbolResolver& linker, ChildrenMapNode* node, ImportStatement* stmt) {
     auto& import_items = stmt->getImportItems();
     if(import_items.empty() && !stmt->is_force_empty_import_items()) {
-        linker.declare(stmt->getTopLevelAlias(), node);
+        auto& alias = stmt->getTopLevelAlias();
+        if(alias.empty()) {
+            // user asked to declare all the symbols
+            for(auto& sym : node->symbols) {
+                linker.declare_or_shadow(sym.first, sym.second);
+            }
+        } else {
+            linker.declare(alias, node);
+        }
         return;
     } else {
         auto& symbols = node->symbols;
@@ -103,7 +111,6 @@ void declareChildren(SymbolResolver& linker, ChildrenMapNode* node, ImportStatem
 }
 
 void TopLevelDeclSymDeclare::VisitImportStmt(ImportStatement* stmt) {
-    if(stmt->getTopLevelAlias().empty()) return;
     switch(stmt->getResultKind()) {
         case ImportResultKind::None:
             linker.error(stmt) << "couldn't import file/module '" << stmt->getSourcePath() << "' because of missing result";