presence | Presence System | Code Editor library
kandi X-RAY | presence Summary
kandi X-RAY | presence Summary
Presence System
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Top functions reviewed by kandi - BETA
- Main entry point
- NewRedis creates a new Redis backend
- Online deletes all IDs associated with ids
- pingdom pingdom
- stat status
- New returns a new session
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Trending Discussions on presence
QUESTION
Motivating background info: I maintain a C++ library, and I spent way too much time this weekend tracking down a mysterious memory-corruption problem in an application that links to this library. The problem eventually turned out to be caused by the fact that the C++ library was built with a particular -DBLAH_BLAH compiler-flag, while the application's code was being compiled without that -DBLAH_BLAH flag, and that led to the library-code and the application-code interpreting the classes declared in the library's header-files differently in terms of data-layout. That is: sizeof(ThisOneParticularClass) would return a different value when invoked from a .cpp file in the application than it would when invoked from a .cpp file in the library.
So far, so unfortunate -- I have addressed the immediate problem by making sure that the library and application are both built using the same preprocessor-flags, and I also modified the library so that the presence or absence of the -DBLAH_BLAH flag won't affect the sizeof() its exported classes... but I feel like that wasn't really enough to address the more general problem of a library being compiled with different preprocessor-flags than the application that uses that library. Ideally I'd like to find a mechanism that would catch that sort of problem at compile-time, rather than allowing it to silently invoke undefined behavior at runtime. Is there a good technique for doing that? (All I can think of is to auto-generate a header file with #ifdef/#ifndef tests for the application code to #include, that would deliberately #error out if the necessary #defines aren't set, or perhaps would automatically-set the appropriate #defines right there... but that feels a lot like reinventing automake and similar, which seems like potentially opening a big can of worms)
ANSWER
Answered 2022-Apr-04 at 16:07One way of implementing such a check is to provide definition/declaration pairs for global variables that change, according to whether or not particular macros/tokens are defined. Doing so will cause a linker error if a declaration in a header, when included by a client source, does not match that used when building the library.
As a brief illustration, consider the following section, to be added to the "MyLibrary.h" header file (included both when building the library and when using it):
QUESTION
ruby '2.7.3' rails (6.1.4.1)
Looks strange:
When I query some (some specific) rows in DB using activerecord and try to assign it to a variable, it raises "nil can't be coerced into Integer"
But when I don't try to assign it to a variable, it works:
...ANSWER
Answered 2022-Feb-15 at 17:50That's related to some unexpected issue related to the use of --nomultiline or IRB.conf[:USE_MULTILINE] = false inside .irbrc file.
To avoid that issue, you can just skip using --nomultiline option, when launching your rails console.
QUESTION
[NOTE: I asked this question based on an older version of Rakudo. As explained in the accepted answer, the confusing output was the result of Rakudo bugs, which have now been resolved. I've left the original version of the Q below for historical reference.]
Raku sometimes prohibits re-binding; both of the following lines
...ANSWER
Answered 2021-Sep-22 at 00:26A decidedly non-authoritative answer. Curiously, like jnthn in your prior Q, it feels natural to answer your questions in reverse order:
Is there any way to tell Raku "don't rebind this name to a new value, no-really-I-mean-it"?
As far as I can tell so far -- purely by testing variations, not by checking roast or the compiler source -- you can and must declare a sigil free symbol, and it must not be one declared with my \symbol ...:
QUESTION
Apparently, discord bots can have mobile status as opposed to the desktop (online) status that one gets by default.
After a bit of digging I found out that such a status is achieved by modifying the IDENTIFY packet in discord.gateway.DiscordWebSocket.identify modifying the value of $browser to Discord Android or Discord iOS should theoretically get us the mobile status.
After modifying code snippets I found online which does this, I end up with this :
...ANSWER
Answered 2022-Feb-07 at 23:03The following works by subclassing the relevant class, and duplicating code with the relevant changes. We also have to subclass the Client class, to overwrite the place where the gateway/websocket class is used. This results in a lot of duplicated code, however it does work, and requires neither dirty monkey-patching nor editing the library source code.
However, it does come with many of the same problems as editing the library source code - mainly that as the library is updated, this code will become out of date (if you're using the archived and obsolete version of the library, you have bigger problems instead).
QUESTION
I was reading the GCC documentation on C and C++ function attributes. In the description of the error and warning attributes, the documentation casually mentions the following "trick":
error ("message")
warning ("message")If the
errororwarningattribute is used on a function declaration and a call to such a function is not eliminated through dead code elimination or other optimizations, an error or warning (respectively) that includes message is diagnosed. This is useful for compile-time checking, especially together with__builtin_constant_pand inline functions where checking the inline function arguments is not possible throughextern char [(condition) ? 1 : -1];tricks.While it is possible to leave the function undefined and thus invoke a link failure (to define the function with a message in
.gnu.warning*section), when using these attributes the problem is diagnosed earlier and with exact location of the call even in presence of inline functions or when not emitting debugging information.
There's no further explanation. Perhaps it's obvious to programmers immersed in the environment, but it's not at all obvious to me, and I could not find any explanation online. What is this technique and when might I use it?
...ANSWER
Answered 2022-Jan-23 at 04:53I believe the premise is to have a compile time assert functionality. Suppose that you wrote
QUESTION
I have the following in test.py:
ANSWER
Answered 2022-Jan-22 at 19:13The syntax you use is recognized as a function stub, not as a function implementation.
Normally, a function stub is written as:
QUESTION
struct A {
int i;
consteval A() { i = 2; };
consteval void f() { i = 3; }
};
constexpr bool g() {
A a;
a.f();
return true;
}
int main() {
static_assert(g());
}
ANSWER
Answered 2022-Jan-12 at 16:20The rule is, from [expr.const]/13:
An expression or conversion is in an immediate function context if it is potentially evaluated and its innermost non-block scope is a function parameter scope of an immediate function. An expression or conversion is an immediate invocation if it is a potentially-evaluated explicit or implicit invocation of an immediate function and is not in an immediate function context. An immediate invocation shall be a constant expression.
Where, an immediate function is simply the term for (from [dcl.constexpr]/2):
A function or constructor declared with the
constevalspecifier is called an immediate function.
From the example:
QUESTION
Like the question says, I am trying to import a CSV with the following function:
...ANSWER
Answered 2021-Dec-23 at 05:30Looks like you want to add passwords to database as is without hashing, and validations have nothing to do with it because they will not change the behavior of the password= function.
You may patch it with another instance variable like:
QUESTION
We have a normal repository, with some code and tests.
One job has 'rules' statement:
...ANSWER
Answered 2021-Aug-27 at 18:48rules:
- if: '$CI_PIPELINE_SOURCE == "merge_request_event"'
when: never
- changes:
- foo/**/*
- foo_scenarios/**/*
- .gitlab-ci.yml
when: always
QUESTION
The code as follows
...ANSWER
Answered 2021-Dec-11 at 11:18Neither definition of the notion of aggregate in C++ Standards refers to the destructor.
For example the definition of an aggregate in C++ 20 (9.4.2 Aggregates) sounds the following way
1 An aggregate is an array or a class (Clause 11) with
(1.1) — no user-declared or inherited constructors (11.4.5),
(1.2) — no private or protected direct non-static data members (11.9),
(1.3) — no virtual functions (11.7.3), and
(1.4) — no virtual, private, or protected base classes (11.7.2).
If to execute this statement in MS VS 2019
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