hpp | Express middleware to protect against HTTP Parameter | Runtime Evironment library

Reviewing, adding some missing code bits:

Here's a build that actually works:

I don't (yet) fully understand the issue, but the cause is the default member initializer of the m_ptr member. It compiles wihout errors if you use the member initializer list instead:

My knowledge comes from e.g. WG22 P0443R12 "A Unified Executors Proposal for C++".

Some differences up front: a work-guard

• does not alter the executor, instead just calling on_work_started() and on_work_finished() on it. [It is possible to have an executor on which both of these have no effect.]
• can be reset() independent of its lifetime, or that of any executor instance. Decoupled lifetime is a feature.

On the other hand, using prefer/require to apply outstanding_work sub-properties:

• modifies existing executors
• notably when copied, all copies will have the same properties. This could be dangerous for something as invasive as keeping an execution context/resources around.

However, not all properties are requirable in the first place. Doing some reconaissance using Ex defined as:

For trivial generators with minimal internal state and code, a small functor or lambda is fine. But as your generator code becomes more complex and requires more state, it becomes less fine. You have to stick more members in your functor type or your lambda specifier. You have bigger and bigger code inside of the function. Etc.

At the most extreme, a co_yield-based generator can hide all of its implementation details from the outside world, simply by putting its definition in a .cpp file. A stateful functor cannot hide its internal state, as its state are members of the type, which the outside world must see. The only way to avoid that is through type-erasure, such as with something like std::function. At which point, you've gained basically nothing over just using co_yield.

Also, co_await can be used with co_yield. Cppcoro's generator type explicitly hoses it, but cppcoro isn't C++20. You can write whatever generator you want, and that generator can support uses of co_await for specific purposes.

Indeed, you can make asynchronous generators, where sometimes you can yield a value immediately, and sometimes you can schedule the availability of a value with some asynchronous process. The code invoking your async generator can co_await on it to extract values from it, rather than treating it like a functor or an iterator pair.

OK, thank you all, for making me understand the process of DLL importing.

As IInspectable and Remy Lebeau said - the import of DLL requires linking with the LIB. Here is more explanations. Also google - "linking a shared library to executable". It is not important whether it is .so or .dll, the principals are the same.

One other important point before I give a solution.

As Remy Lebeau said: several functions

didn't exist yet (or were introduced shortly before) when BCB5 was released

Fix for makefile

So here is a simple Linux specific code that checks whether a specified target file is open by the current process (using --std=c++17 for dir listing but any way can be used of course).

I've tried to get a handle on this problem using just the DE-9IM that Boost Geometry implements: https://godbolt.org/z/KWzvzExr7 which outputs https://pastebin.ubuntu.com/p/9ck6gcPK5P/

To understand why, read this (earlier) post or this (nicer) one.

To make a concrete example:

• suppose main.o defines main(), fn(), and references a() and b().
• libA.a contains a.o which defines a()
• libB.a contains b.o which defines b(), and also a1.o which defines a() and fn().

Now, if you link with gcc main.o -lA -lB, the link will succeed (a.o from libA.a and b.o from libB.a will be selected into the link, and no symbol conflicts will arise. Notably, a1.o from libB.a will not be selected into the link).

But if you link with gcc main.o -lB -lA, then fn() will be multiply defined (because both a1.o and b.o from libB.a will be selected into the link, but the definition of fn() in a1.o will be in conflict with the definition of fn() in main.o).