[phase 1] Add areg:: root namespace and organize sub-namespaces

[aregtech]

Important

Refactoring changes should be rebased and merged against this branch:
feature/655-api-modernization-and-refactoring

Summary

Wrap the entire AREG SDK framework in an areg:: root namespace, and organize internal modules into sub-namespaces that replace the current NE prefix convention.

Current state

All classes and functions live in the global namespace. Module grouping is done through filename prefixes:

// Current — global namespace, NE prefix
#include "areg/base/NECommon.hpp"
NECommon::INVALID_INDEX;
NEString::CharPos pos = NEString::START_POS;

Target state

// After — proper namespaces
#include "areg/base/common.hpp"
areg::common::INVALID_INDEX;
areg::string::CharPos pos = areg::string::START_POS;

// Or with using-directive
using namespace areg;
common::INVALID_INDEX;

Namespace mapping

Current prefix/file	New namespace
NECommon	areg::common
NEString	areg::string
NEMath	areg::math
NEMemory	areg::memory
NESocket	areg::net (or areg::socket)
NEUtilities	areg::util
NEService	areg::service
NERegistry	areg::registry
NELogging	areg::logging
All classes (e.g., String, Thread, Component)	areg:: root

Scope

Files to modify

• framework/areg/base/ — 53 headers + corresponding .cpp files
• framework/areg/component/ — 37 headers + corresponding .cpp files
• framework/areg/ipc/ — all headers and sources
• framework/areg/logging/ — all headers and sources
• framework/areg/persist/ — all headers and sources
• framework/areg/appbase/ — all headers and sources
• framework/areg/system/ — all headers and sources

Work order

Process module by module. Each module can be a separate PR:

1. framework/areg/base/
2. framework/areg/component/
3. framework/areg/ipc/
4. framework/areg/logging/
5. framework/areg/persist/
6. framework/areg/appbase/
7. framework/areg/system/

Rules

• Every public header gets namespace areg { wrapper
• NE-prefixed utility namespaces become real sub-namespaces
• Platform-specific private implementations (e.g., posix/, win32/) also go inside areg:: but remain in private/ directories
• Macros (GEMacros.h, GEGlobal.h) remain outside namespaces (macros are not namespace-aware), but filenames should drop the GE prefix
• Internal linkage (private/ directories) uses areg::internal:: or anonymous namespaces

Acceptance criteria

• All public classes and functions are inside namespace areg
• All NE-prefixed utility classes are converted to sub-namespaces
• Project compiles on all supported platforms
• All existing unit tests pass
• No symbols remain in the global namespace except macros

[caliph1998]

Hi @aregtech
I was interested in contributing to this project and I'm looking at this Issue. Quick question for clarification:

For example, after creating the sub-namespace areg::logging out of NELogging, do you want classes like LogConfiguration and LogScope (which are in the global namespace) to be wrapped by the areg:: namespace or areg::logging::?
Currently they are declared in the areg/logging directory but not wrapped by the NELogging namespace

[aregtech]

Hi @caliph1998,

thank you for joining the refactoring process.

Quick answer: it should be in the areg namespace.

All classes and namespaces will be placed under the areg namespace. The visibility of this namespace will be controlled by a macro, allowing compilation with or without the areg namespace. I am preparing a commit that introduces this macro and applies it consistently across all framework source files. It will be submitted to the main refactoring branch:
https://github.com/aregtech/areg-sdk/tree/feature/655-api-modernization-and-refactoring

At the moment, there is an ongoing discussion about coding style.
You are very welcome to join the discussion. After it is finalized, a formal coding style document will be published. While the namespace topic is not directly related to coding style, the upcoming commit is quite large. I was experimenting with .clang-format, which resulted in modifications many files. To avoid merge conflicts, I recommend waiting until this commit is merged.

Notes:

• feature/655-api-modernization-and-refactoring is the main refactoring branch.
• Any refactoring branch should be rebased onto this branch.
• All refactoring changes should be merged into this branch.

Please wait a little; I will inform you once the changes are committed.

[caliph1998]

@aregtech
No worries I'll wait

[aregtech]

hi @caliph1998 ,
I have added following macro:

#if defined(AREG_NAMESPACE) && (AREG_NAMESPACE == 0)
    #undef AREG_NAMESPACE_BEGIN
    #undef AREG_NAMESPACE_END
    #undef AREG_NAMESPACE_USE

    #define AREG_NAMESPACE_BEGIN
    #define AREG_NAMESPACE_END
    #define AREG_NAMESPACE_USE
#else // defined(AREG_NAMESPACE)
    #undef AREG_NAMESPACE_BEGIN
    #undef AREG_NAMESPACE_END
    #undef AREG_NAMESPACE_USE

    #define AREG_NAMESPACE_BEGIN    namespace areg {
    #define AREG_NAMESPACE_END      }
    #define AREG_NAMESPACE_USE      using namespace areg;
#endif // defined(AREG_NAMESPACE)

this will show / hide namespace areg
The task would be in every source file to add AREG_NAMESPACE_BEGIN at the begin and AREG_NAMESPACE_END at the end.

If you make changes, please branch from feature/655-api-modernization-and-refactoring and merge there.

[caliph1998]

@aregtech
yea I'm working on it to use your macros. My plan is to use AREG_NAMESPACE_BEGIN and AREG_NAMESPACE_END for the .hpp files and AREG_NAMESPACE_USE for the .cpp files. But there are some std::hash specializations going on in the .hpp files that will create areg::std:: namespace by mistake if I just wrap .hpp files in AREG_NAMESPACE_BEGIN/END. I'm working on it

[aregtech]

hi @caliph1998
thank you!
actually, if it works without std then i would prefer to remove it and leave only areg::
Otherwise, it should be taken out of AREG_NAMESPACE_END
This would be cleaner and less confusing. The namespace areg::std looks confusing

[caliph1998]

@aregtech
It's more than confusing it's unbuildable haha! areg::std should not happen at all. I'm seeing into careful wrapping of these files so that namespace std:: { std:: hash<> ...} code blocks would never be wrapped by AREG_NAMESPACE_BEGIN/END by accident