From 0051e6e1af5baba158d75f12a3638429997b4964 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dietmar=20K=C3=BChl?= <dietmar.kuehl@me.com>
Date: Mon, 23 Mar 2026 20:32:35 +0000
Subject: [PATCH 1/2] added a TLS using example for task

---
 examples/CMakeLists.txt |  1 +
 examples/alloc-2.cpp    | 83 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 84 insertions(+)
 create mode 100644 examples/alloc-2.cpp

diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index de068e5..a1539d0 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -33,6 +33,7 @@ if(NOT MSVC)
         APPEND ALL_EXAMPLES
         task-sender
         alloc-1
+        alloc-2
         bulk
         c++now-allocator
         c++now-cancel
diff --git a/examples/alloc-2.cpp b/examples/alloc-2.cpp
new file mode 100644
index 0000000..0213cf4
--- /dev/null
+++ b/examples/alloc-2.cpp
@@ -0,0 +1,83 @@
+// examples/alloc-1.cpp                                               -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#include <beman/execution/task.hpp>
+#include <beman/execution/execution.hpp>
+#include <functional>
+#include <iostream>
+#include <memory>
+#include <memory_resource>
+#include <new>
+#include <cstdlib>
+#include <utility>
+
+namespace ex = beman::execution;
+
+// ----------------------------------------------------------------------------
+
+struct tls_allocator
+    : std::pmr::polymorphic_allocator<std::byte> {
+    thread_local static std::pmr::memory_resource* alloc;
+
+    tls_allocator(): std::pmr::polymorphic_allocator<std::byte>(alloc) {}
+
+    static void set(std::pmr::memory_resource* a) { alloc = a; }
+};
+thread_local std::pmr::memory_resource* tls_allocator::alloc{std::pmr::new_delete_resource()};
+
+// ----------------------------------------------------------------------------
+
+void* operator new(std::size_t n) {
+    auto p = std::malloc(n);
+    std::cout << "    global new(" << n << ")->" << p << "\n";
+    return p;
+}
+void operator delete(void* ptr) noexcept {
+    std::cout << "    global operator delete(" << ptr << ")\n";
+    std::free(ptr);
+}
+void operator delete(void* ptr, std::size_t size) noexcept {
+    std::cout << "    global operator delete(" << ptr << ", " << size << ")\n";
+    std::free(ptr);
+}
+
+struct resource : std::pmr::memory_resource {
+    void* do_allocate(std::size_t n, std::size_t) override {
+        auto p{std::malloc(n)};
+        std::cout << "    resource::allocate(" << n << ")->" << p << "\n";
+        return p;
+    }
+    void do_deallocate(void* p, std::size_t n, std::size_t) override {
+        std::cout << "    resource::deallocate(" << p << ", " << n << ")\n";
+        std::free(p);
+    }
+    bool do_is_equal(const std::pmr::memory_resource& other) const noexcept override { return this == &other; }
+};
+
+// ----------------------------------------------------------------------------
+
+using allocator_type = tls_allocator;
+struct alloc_env {
+    using allocator_type = ::allocator_type;
+};
+template <typename T = void>
+using a_task = ex::task<T, alloc_env>;
+
+a_task<int> async_fun(int value) { co_return value; }
+
+int main(int ac, char*[]) {
+    resource       res{};
+
+    std::cout << "not setting up an allocator:\n";
+    ex::sync_wait([ac]() -> a_task<> {
+        auto result{co_await async_fun(ac)};
+        std::cout << "    result=" << result << "\n";
+    }());
+
+    std::cout << "setting up an allocator:\n";
+    tls_allocator::set(&res);
+    ex::sync_wait([ac]() -> a_task<> {
+        auto result{co_await async_fun(ac)};
+        std::cout << "    result=" << result << "\n";
+    }());
+}

From ebc86d46f0887a13f68d72bfce66b338c5606cf0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dietmar=20K=C3=BChl?= <dietmar.kuehl@me.com>
Date: Mon, 23 Mar 2026 20:34:32 +0000
Subject: [PATCH 2/2] fix formatting

---
 examples/alloc-2.cpp | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/examples/alloc-2.cpp b/examples/alloc-2.cpp
index 0213cf4..1877661 100644
--- a/examples/alloc-2.cpp
+++ b/examples/alloc-2.cpp
@@ -15,11 +15,10 @@ namespace ex = beman::execution;
 
 // ----------------------------------------------------------------------------
 
-struct tls_allocator
-    : std::pmr::polymorphic_allocator<std::byte> {
+struct tls_allocator : std::pmr::polymorphic_allocator<std::byte> {
     thread_local static std::pmr::memory_resource* alloc;
 
-    tls_allocator(): std::pmr::polymorphic_allocator<std::byte>(alloc) {}
+    tls_allocator() : std::pmr::polymorphic_allocator<std::byte>(alloc) {}
 
     static void set(std::pmr::memory_resource* a) { alloc = a; }
 };
@@ -66,7 +65,7 @@ using a_task = ex::task<T, alloc_env>;
 a_task<int> async_fun(int value) { co_return value; }
 
 int main(int ac, char*[]) {
-    resource       res{};
+    resource res{};
 
     std::cout << "not setting up an allocator:\n";
     ex::sync_wait([ac]() -> a_task<> {