Add Json write support

CHANGELOG.md

@@ -1,6 +1,7 @@
 # 0.10.0
 
 * Bumped minimum GCC to 13.
+* Added `mbo/json` which adds JSon write support for almost any structured type. If anything is missing it can easily be added on the client side.
 * Added direct support for `-fno-exceptions` irrespective of config setting.
 * Added support for ASAN symbolizer with `--config=clang`.
 * Added AbslStringify and hash support to `NoDestruct`, `RefWrap`, `Required`.

mbo/json/BUILD.bazel

@@ -0,0 +1,49 @@
+# SPDX-FileCopyrightText: Copyright (c) The helly25 authors (helly25.com)
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+load("@rules_cc//cc:defs.bzl", "cc_library", "cc_test")
+
+package(default_visibility = ["//visibility:private"])
+
+alias(
+    name = "json",
+    actual = "json_cc",
+)
+
+cc_library(
+    name = "json_cc",
+    hdrs = ["json.h"],
+    deps = [
+        "//mbo/config:require_cc",
+        "//mbo/types:cases_cc",
+        "//mbo/types:compare_cc",
+        "//mbo/types:stringify_cc",
+        "//mbo/types:traits_cc",
+        "//mbo/types:variant_cc",
+        "@abseil-cpp//absl/container:flat_hash_map",
+    ],
+)
+
+cc_test(
+    name = "json_test",
+    srcs = ["json_test.cc"],
+    deps = [
+        ":json_cc",
+        "//mbo/testing:matchers_cc",
+        "//mbo/types:typed_view_cc",
+        "@googletest//:gtest",
+        "@googletest//:gtest_main",
+    ],
+)