Function tutorial

tutorials/integration/cpp/16_sandbox.cpp:143–321

#define SCRIPT_NAME "/tutorials/integration/cpp/16_sandbox.das"

void tutorial() {
    TextPrinter tout;
    string scriptPath = getDasRoot() + SCRIPT_NAME;

    // ================================================================
    // Demo 1: No restrictions (normal compilation)
    // ================================================================
    tout << "=== Demo 1: No restrictions ===\n";
    {
        auto fAccess = make_smart<FsFileAccess>();
        CodeOfPolicies policies;
        run_script("Normal mode", scriptPath, fAccess, policies, tout);
    }

    // ================================================================
    // Demo 2: CodeOfPolicies restrictions
    // ================================================================
    tout << "\n=== Demo 2: Policies — no_unsafe ===\n";
    {
        auto fAccess = make_smart<FsFileAccess>();

        // Policy: forbid unsafe blocks
        CodeOfPolicies policies;
        policies.no_unsafe = true;

        // The safe script should compile fine
        run_script("Safe script with no_unsafe", scriptPath,
                   fAccess, policies, tout);

        // An unsafe script should fail to compile
        tout << "\n";
        auto fAccessUnsafe = make_smart<FsFileAccess>();
        fAccessUnsafe->setFileInfo("unsafe_test.das",
            make_unique<TextFileInfo>(UNSAFE_SCRIPT,
                                     uint32_t(strlen(UNSAFE_SCRIPT)),
                                     false));
        run_script("Unsafe script with no_unsafe",
                   "unsafe_test.das", fAccessUnsafe, policies, tout);
    }

    // ================================================================
    // Demo 3: Memory limits
    // ================================================================
    tout << "\n=== Demo 3: Memory limits ===\n";
    {
        auto fAccess = make_smart<FsFileAccess>();

        CodeOfPolicies policies;
        policies.stack = 8 * 1024;                    // 8 KB stack
        policies.max_heap_allocated = 1024 * 1024;    // 1 MB heap
        policies.max_string_heap_allocated = 256*1024; // 256 KB strings

        tout << "  Stack:       " << policies.stack << " bytes\n";
        tout << "  Max heap:    " << policies.max_heap_allocated
             << " bytes\n";
        tout << "  Max strings: " << policies.max_string_heap_allocated
             << " bytes\n";