Date: Fri, 10 Apr 2026 10:28:00 +0200
On Fri, Apr 10, 2026 at 9:48 AM Muneem via Std-Proposals <
std-proposals_at_[hidden]> wrote:
>
> While you are exceptionally goated and up to that, there are issues with
> your code that are understandable since it's a metaprogramming mess that
> would make anyone do mistakes:
> [...] My code was to show that without language support, you will end up
> writing messy code.
>
Somebody has to write the code for your new feature. Either the code is
inside the compiler written in either existing C++ (clang) or C (GCC) or it
is written in a library. I bet with you that all the solutions are rather
messy. It actually doesn't matter how messy the solution is inside the STL
because the user does not have to write or read it. The perceived
messiness from your point of view is not relevant for standardization as
long as the compiler can easily understand it.
I have a counterpoint to make: More complicated code inside the compiler
has the potential to introduce severe bugs–even for features that work
perfectly fine now. I propose to write the simplest compiler possible so
that we have the fewest bugs inside the compiler and programmers can rely
on the compiler. If your new type is implemented in the compiler we will
have new compiler bugs. If, however, in an STL implementation of your new
type there is a bug, the bug will not spread to other code not using it. It
is also easier to fix the bug (in the messy metaprogramming) because it is
isolated to a single header file (and not spread throughout the entire
compiler source code).
The worst part is that with "metaprogramming" you only mean "template
metaprogramming". "Reflection" is the new type of "metaprogramming". And
despite the name (or different definitions of the term 'reflection'), we
cannot just inspect source code (using reflectors), but also generate new
code (especially in future C++ versions). There is a lot of work being done
to simplify metaprogramming and make it less messy. (Template
metaprogramming is a form of functional programming. Reflection, on the
other hand, looks a lot more like regular C++ code (imperative, OO
programming). BTW, the term metaprogramming is traditionally not applied to
just templated classes, but it requires computations to be done with
templates.)
std-proposals_at_[hidden]> wrote:
>
> While you are exceptionally goated and up to that, there are issues with
> your code that are understandable since it's a metaprogramming mess that
> would make anyone do mistakes:
> [...] My code was to show that without language support, you will end up
> writing messy code.
>
Somebody has to write the code for your new feature. Either the code is
inside the compiler written in either existing C++ (clang) or C (GCC) or it
is written in a library. I bet with you that all the solutions are rather
messy. It actually doesn't matter how messy the solution is inside the STL
because the user does not have to write or read it. The perceived
messiness from your point of view is not relevant for standardization as
long as the compiler can easily understand it.
I have a counterpoint to make: More complicated code inside the compiler
has the potential to introduce severe bugs–even for features that work
perfectly fine now. I propose to write the simplest compiler possible so
that we have the fewest bugs inside the compiler and programmers can rely
on the compiler. If your new type is implemented in the compiler we will
have new compiler bugs. If, however, in an STL implementation of your new
type there is a bug, the bug will not spread to other code not using it. It
is also easier to fix the bug (in the messy metaprogramming) because it is
isolated to a single header file (and not spread throughout the entire
compiler source code).
The worst part is that with "metaprogramming" you only mean "template
metaprogramming". "Reflection" is the new type of "metaprogramming". And
despite the name (or different definitions of the term 'reflection'), we
cannot just inspect source code (using reflectors), but also generate new
code (especially in future C++ versions). There is a lot of work being done
to simplify metaprogramming and make it less messy. (Template
metaprogramming is a form of functional programming. Reflection, on the
other hand, looks a lot more like regular C++ code (imperative, OO
programming). BTW, the term metaprogramming is traditionally not applied to
just templated classes, but it requires computations to be done with
templates.)
Received on 2026-04-10 08:28:39