That’s cheating
#development
lyric mountain
I mean, you still have to write the logic yourself, antlr simply identifies and iterates the elements
wheat mesa
I don’t think antlr is used too much in many spots nowadays
It’s cool to learn how it works but I think it’s important to know how to write both a lexer and parser by hand
lyric mountain
antlr is surely used nowadays wdym
lyric mountain
just use an unsigned 32-bit integer <:mmLol:356831697385422848>
bank account goes from -$200.00 to $42,949,472.96 overnight
stonks
magic sonnet
Tryna slide?!
sharp geyser
Honestly making a lexer and parser with my current knowledge would be ludicrous
I still yet to fully grasp language specific features like classes, pointers, references, and anything else beyond basic datatypes and rudamentary knowledge on functions (as I am pretty sure functions are not entirely like what I am used to in languages like js)
I am severely lacking
wheat mesa
Honestly making a lexer and parser with my current knowledge would be ludicrous
It’s not as hard as you think tbh
Lexing is basically just a fancy word for “loop over characters to see if I recognize something”
And attaching metadata to each of those characters (line number, column number, if they are a keyword, etc)
sharp geyser
I mean yea it might not be hard, but I also am not confident to tackle something like that, nor do I know where to start. I understand it would give me valuable knowledge and a learning experience.
wheat mesa
Parsing is a bit more complex but for basic math expressions it’s quite simple
Fair
Well if you end up finishing that calculator thingy lmk if you want a little code review 😉
(Or if you need help with the “correct” approach)
sharp geyser
Honestly I am stuck on where to proceed so I dont see myself getting far right now.
wheat mesa
What are u stuck on
sharp geyser
I also have work in 18 minutes
sharp geyser
What are u stuck on
Right now I am stuck on how to even evaluate the expression
Ophidian gave some helpful advice
but I don't really know how to actually implement something like what he suggested with C++
wheat mesa
Are you looking to be accurate for order of operations?
Or do you just want to evaluate sequentially
wheat mesa
Order of operations is the hardest thing to do in a calculator like this, but if you don’t care about order of operations then it should be pretty trivial
sharp geyser
I'd like to eventually implement following pemdas
wheat mesa
Pemdas is likely going to need a proper parser or something like the shunting yard algorithm to implement
Not too good of a way around it
wheat mesa
Antlr is cheating if he wants to learn C++ with this project tho :c
lyric mountain
but the syntax is quite simple to understand
lyric mountain
Antlr is cheating if he wants to learn C++ with this project tho :c
not what I mean
sharp geyser
I'd rather stick to do it my own
lyric mountain
the matcher declaration, can help giving an idea on how to sequence your matches
not to use antlr or anything
after u have an image of the chain you're trying to build, u can focus on implementation
wheat mesa
If you want a good bit of practice you can make a RPN evaluator with a simple std::list and looping over characters
That way PEMDAS isn’t a giant barrier since there is no order of operations for RPN
2 2 3 + * is equal to 10 for example
3 + 2 = 5
5 * 2 = 10
sharp geyser
Never seen an eqaution like that
wheat mesa
It’s called reverse Polish notation
It can be trivially evaluated with a stack of operands and operators
sharp geyser
So basically all the numbers come first and the operators go after
and it evalutates whatever two numbers are closest to the first operators
then continues down the list?
wheat mesa
Basically
If you encounter a number, push it on to the operand stack
If you encounter a operator, pop 2 numbers from the operand stack and push the result back on to the operand stack
wheat mesa
It’s easy to implement but still lets you learn a bit before going into evaluating “normal” notation
sharp geyser
I will try and implement something of the sort after work
digital swan
bump 😁
magic sonnet
This is my code: https://haste.reversed.dev/p/lVW8XC.js
I get this error;
DiscordAPIError[50035]: Invalid Form Body
8[APPLICATION_COMMANDS_DUPLICATE_NAME]: Application command names must be unique
Why?
deft wolf
You already have a command with this name
magic sonnet
The command has 2 sub commands though in the same file.
deft wolf
But this most likely has nothing to do with this exact command. Check where exactly this error comes from, I assume it's when registering commands. If you have two of the same commands with the same name, change them to something else
lyric mountain
This is my code: https://haste.reversed.dev/p/lVW8XC.js
I get this error;
Discor...
why are you checking twice for every subcommand?
grim aspen
why are you checking twice for every subcommand?
i'm curious too
magic sonnet
why are you checking twice for every subcommand?
I guess I forgot to remove that part when I was moving both files to one, but still gives the same error.
grim aspen
lemme guess, there's a missing '}'
magic sonnet
I initially didn't think of adding a reminder list command until after
grim aspen
yeah you have a duplicate sub command
magic sonnet
The list one just doesn't register only the add sub command does
grim aspen
the problem is that you have a duplicate command somewhere in your index.js file
that's what it's saying
magic sonnet
Ahhhhh I found that
magic sonnet
But this most likely has nothing to do with this exact command. Check where exac...
When I remove the reminders file I get no problems when I add it, then I get the error.
It ended up being because I forgot to delete the old files from the my repo before making the new one.
compact pier
Wherer should I store one time password? Should I use redis for that?
lyric mountain
wdym one-time password?
if you're going to use it once and never again, dont store it
compact pier
I mean like a email confirmation code
so I need to store the generated code somewhere to check it
lyric mountain
hm, I was going to say "you dont store those", but technically u do need to keep it for a while
you can keep it in memory for a while and then discard afterwards
compact pier
you think? it sounds like unefficient tho
lyric mountain
it's the other way around
you'll be storing what, 5 characters per verification request?
compact pier
yes
lyric mountain
a simple map/dictionary will do
compact pier
and user id
lyric mountain
with userid-code pairs
once the time elapses, or the user verifies successfully, u remove the entry
lyric mountain
there are expiring-map libs out there, redis has this too iirc
lyric mountain
do you think array will be better? like just `userid-code`
map
compact pier
okok
lyric mountain
maps are O(1) for key accesses
since you'll be retrieving the entry based on userid, it'll be the best option
compact pier
Ok understood, thank you
lyric mountain
yw
wraith merlin
I added my bot but its not showing up, i did it yesterday
sharp geyser
Its likely still in queue then
wraith merlin
Im also trying to get the token for my Topgg thing
deft wolf
You have to wait until they approve your bot
If your bot is accepted, you will find your token in the "webhook" tab when editing your bot
sharp geyser
@wheat mesa So here's my thought process on how to achieve this using reverse polish notations. I have 2 lists, one for operands, and the other for operators. Then I will evaluate that by taking the last two entry in the operands and the first in the operators and evaluating it then assigning it to a temp variable. Now if there are no operands left, then it stops evaluating and gives the final result.
radiant kraken
<@173489654144696320> So here's my thought process on how to achieve this using ...
yes, this works
wheat mesa
Yup that’s pretty much the algorithm
The only reason stacks are used is because it’s more efficient than vectors
(But if by list you mean std::list then that’s a linkedlist so it works as a stack for this impl)
sharp geyser
(But if by list you mean std::list then that’s a linkedlist so it works as a sta...
Oh I was using std::vector
wheat mesa
I mean it still works, it’s just a little more inefficient
radiant kraken
I mean it still works, it’s just a little more inefficient
just use int * for lists 
sharp geyser
@wheat mesa @radiant kraken @earnest phoenix
std::string expression;
std::cout << "What would you like to evaluate?\n";
std::getline(std::cin, expression);
std::vector<std::string> tokens;
std::istringstream stream(expression);
std::string token;
std::vector<int> operands;
std::vector<std::string> operators;
while (stream >> token) {
tokens.push_back(token);
}
char* endPtr;
for(const std::string& token : tokens) {
long operand = std::strtol(token.c_str(), &endPtr, 10);
if (*endPtr == '\0') {
operands.push_back(operand);
} else {
operators.push_back(token);
}
}
How do you like my code for parsing the input into ints. I don't think I can use strings for operators but for now idc.
radiant kraken
looks really good for a beginner
sharp geyser
stackoverflow was not giving me proper answers
it was only giving int -> string not string -> int
radiant kraken
oh well
sharp geyser
I also don't really understand how strtol works
radiant kraken
it looks good enough
sharp geyser
I have a vague understanding on what it does
radiant kraken
I also don't really understand how strtol works
strtol stands for string to long
sharp geyser
but no idea why I have to use a char pointer
sharp geyser
strtol stands for string to long
gotcha
radiant kraken
sharp geyser
OH okay
so if endptr is not a nullptr it will set the value of endptr to the first character after the number
which is why I check for \0
to see if its successful
radiant kraken
so if endptr is not a nullptr it will set the value of endptr to the first chara...
exactly
sharp geyser
So what exactly is a nullptr then
Cause reading on it I don't quite get it
I understand its better than using 0 or NULL
sharp geyser
so when is the appropriate time to use nullptr?
radiant kraken
in strtol?
sharp geyser
Should I use it there?
I figured it'd be good to not use it since I need to verify if the conversion was successful
and if it fails to convert something wont it error if nullptr is used?
radiant kraken
Should I use it there?
no
you pass in nullptr/NULL to the second argument (endptr) if you don't need to parse the next integers following the current one
radiant kraken
it's only useful when you want this:
char a[] = "69";
long sixtynine = strtol(a, NULL, 10);
I see
On another note
What would be the best way to get the last x elements of a vector
for example say I wanted the last 2
radiant kraken
for example say I wanted the last 2
std::vector<int> a = ...;
std::vector<int>::size_type length = a.size();
// a[length - 1];
// a[length - 2];
```?this?
sharp geyser
I could do that
hm
I just need to use a loop of some kind so it always gets the last two if possible and keeps evaluating the expression until it reaches the end
I was thinking of using a while loop
radiant kraken
yup
sharp geyser
```cpp
std::vector<int> a = ...;
std::vector<int>::size_type length = a.size();
...
Oh wait this isn't going to work
Because if it gets down to there only being operand left then it could cause errors or UB
sharp geyser
#include <iostream>
#include <string>
#include <vector>
#include <sstream>
int main() {
std::string expression;
std::cout << "What would you like to evaluate?\n";
std::getline(std::cin, expression);
std::vector<std::string> tokens;
std::istringstream stream(expression);
std::string token;
std::vector<int> operands;
std::vector<std::string> operators;
while (stream >> token) {
tokens.push_back(token);
}
char* endPtr;
for(const std::string& token : tokens) {
long operand = std::strtol(token.c_str(), &endPtr, 10);
if (*endPtr == '\0') {
operands.push_back(operand);
} else {
operators.push_back(token);
}
}
int result = 0;
for(int i = 0; i < operands.size(); i++) {
int op = operands.back();
if(operators.front() == "+") {
result += op;
} else if(operators.front() == "-") {
result -= op;
} else if(operators.front() == "*") {
result *= op;
} else if(operators.front() == "/") {
result /= op;
}
}
std::cout << result << std::endl;
// std::copy(operands.begin(), operands.end(), std::ostream_iterator<int>(std::cout, " "));
// std::copy(operators.begin(), operators.end(), std::ostream_iterator<std::string>(std::cout, " "));
return 0;
}
in theory this seemed fine, in practice not so much
Then I remembered for the reverse polish notation to work, I need to take the last two numbers and not just the first one
😔
radiant kraken
switch case statements only accept ints
switch cases work on characters tho
sharp geyser
Honestly
I am just dumbfounnded on what to do
Cause I can easily get the last two, but on how to actually do the evaluations is beyond me
radiant kraken
Cause I can easily get the last two, but on how to actually do the evaluations i...
wdym?
sharp geyser
Like I can get the last to operands
but on how to evaluate them based on the first operator I have no idea
I cant seem to figure it out
radiant kraken
I cant seem to figure it out
i have an idea in mind
but i dont really have the time to code it rn 
sharp geyser
You could explain it instead
radiant kraken
wait
something like this @sharp geyser
char * input = ...;
char * endptr = input;
bool first = true;
long last;
while (1) {
long a = std::strtol(endptr, &endptr, 10);
char Operator = get_next_operator(&endptr);
if (first) {
first = false;
long b = std::strtol(endptr, &endptr, 10);
last = execute(Operator, a, b);
} else {
last = execute(Operator, last, a);
}
if (*endptr == '\0') break;
}
// result is `last`
its a bit hard to explain
sharp geyser
Also
I wasn't stuck on getting the last two I was stuck on actually how to execute it
radiant kraken
I wasn't stuck on getting the last two I was stuck on actually how to execute it
why is that?
sharp geyser
Because I dont see how I can execute the equation?
sharp geyser
its a reverse polish notation. I use push_back to add the operands to the vector
so I get the last 2 and take the first operator
sharp geyser
Basically it goes
2 2 3 + *
2 + 3 = 5
5 * 2 = 10
radiant kraken
hmmmmmmm
sharp geyser
Use of undeclared identifier 'evaluate'
radiant kraken
obviously it was a prototype
sharp geyser
clearly exists
sharp geyser
obviously it was a prototype
Oh I know
but I made my own evaluate function
but it is saying it no exist
Wait
do I have to put the function before the main function
is that how C++ work
radiant kraken
maybe something like this? ```
first = true
length = operands.size()
for i = 0; i < length; i++
b = operands.back()
operands.pop_back()
a = operands.back()
operands.pop_back()
operator = operators.front()
operators.pop_front()
operands.push_back(execute(operator, a, b))
result = operands.back()
I never thought about just overwriting what the operands vector is
That is actually genuis
radiant kraken
i'm so sorry that it took me a while to understand your problem lmao
@earnest phoenix what do you think?
earnest phoenix
<@173489654144696320> <@661200758510977084> <@456226577798135808>
```c++
st...
Good enough, note that your const std::string& token declaration shadows the previous declaration
radiant kraken
C++ is harmful
sharp geyser
@real rose fix automod
radiant kraken
to me at least
earnest phoenix
sharp geyser
uh oh spaghettio
earnest phoenix
<@456226577798135808> what do you think?
What exactly is going on?
sharp geyser
What exactly is going on?
Instead of making a normal math calculator
I am using reverse polish notation
:D
radiant kraken
What exactly is going on?
sharp geyser
Basically it goes
2 2 3 + *
2 + 3 = 5
5 * 2 = 10
Which has really simple rules
earnest phoenix
radiant kraken
what do u think of my pseudocode?
earnest phoenix
Why would you do that?
radiant kraken
to suffer ig
sharp geyser
In theory it sounded okay
radiant kraken
tho its really good for learning about stacks
sharp geyser
It made sense to me, probably not the best way to do it but hey
if it works it works
I wonder why its exiting tho
Apparently a seg fault or access violation
sharp geyser
radiant kraken
could be a problem on how you're getting the operands and operators
or was it working before?
earnest phoenix
It's not entirely horrendous, just very inefficient to handle actual compound equations and such, the proper way to handle the discovery of operands and their relative binary expressions is to peek through the characters in the token stream, and going by the rules of operator precedence, construct the structure of the equation from either the left or the right side
And if nothing fits in there, throw a syntax error
radiant kraken
wait what's ur code
earnest phoenix
uh oh spaghettio
Use the LLDB debugger
sharp geyser
Use the LLDB debugger
I was going to but I couldn't figure out how to get it to use that one
Is it not this one?
earnest phoenix
Open C:\Program Files\LLVM\bin, what do you see?
sharp geyser
sharp geyser
yes
earnest phoenix
Try running lldb --version in the console
earnest phoenix
Well there you go, you need to install Python since LLDB uses it
radiant kraken
wait what's ur code
@sharp geyser
sharp geyser
one sec
earnest phoenix
Damn Hastebin has changed a lot
radiant kraken
hmmmm reinterpret_cast<const char *>(token)
this rings a red flag to me
wait
nvm
radiant kraken
before the for(int i = 0; i < operands.size(); i++) loop, what does std::cout << operands << '\n' << operators << std::endl; yield?
does it work as expected
sharp geyser
well you can't print vectors like that
earnest phoenix
Did you install Python yet? 
earnest phoenix
What does it say?
sharp geyser
Now then to answer null's question, same shit happens even before the for loop
sharp geyser
What does it say?
Same thing
radiant kraken
Now then to answer null's question, same shit happens even before the for loop
then the problem is not on the last for loop
sharp geyser
Its likely the casting to char *
thats the only thing I can think of that i've done differently
but strtol takes in a std::string or char* not char
radiant kraken
as i said before, maybe it's something wrong with this ```cpp
for(const char& token : tokens) {
long operand = std::strtol(reinterpret_cast<const char *>(token), &endPtr, 10);
i'm not really that big into C++, is there anything wrong with this? @earnest phoenix
sharp geyser
thats what I am thinking
radiant kraken
i'm more of a C dev than C++ 
sharp geyser
@earnest phoenix So I can't even install python 3.10 anymore its in a security release only stage
and the security release doesn't even have the python310.dll
radiant kraken
imo it's better to just try to solve the segfault ourselves without a debugger first
the problem is most likely on that for loop
earnest phoenix
<@456226577798135808> So I can't even install python 3.10 anymore its in a secur...
Can you open the directory Python was installed to?
sharp geyser
Already have it open
sharp geyser
imo it's better to just try to solve the segfault ourselves without a debugger f...
So yea it was the casting
I did something that was probably worse and got it to work
earnest phoenix
Already have it open
What is in there?
radiant kraken
I did something that was probably worse and got it to work
what was it?
sharp geyser
what was it?
char myCharArray[2];
myCharArray[0] = token;
myCharArray[1] = '\0';
for(const char& token : tokens) {
long operand = std::strtol(myCharArray, &endPtr, 10);
no idea what it does
but did it to see if it would fix the problem
earnest phoenix
Use the "Windows Installer (64-bit)"
https://www.python.org/downloads/release/python-31010/
radiant kraken
```c++
char myCharArray[2];
myCharArray[0] = token;
myCharArray[1] =...
ayyy that's actually a really good way to fix the problem
earnest phoenix
I'm not exactly sure why LLDB doesn't use the latest Python DLL, but eh
sharp geyser
I bet
radiant kraken
is the result as expected?
sharp geyser
I just don't know what it does
sharp geyser
is the result as expected?
Nope
new error
it aborts because back is called on an empty vector
radiant kraken
lmao
sharp geyser
probably the operators vector
earnest phoenix
Note that you were casting a reference to a pointer, this is not entirely valid
sharp geyser
As there is 3 in the operands 2 in the operators
so its trying to pull a 3rd from the operators when it doesn't exist
radiant kraken
not really sure what this does```cpp
std::vector<char> tokens;
std::istringstream stream(expression);
while (stream >> token) {
tokens.push_back(token);
}
what is tokens?
does it just split by whitespace
sharp geyser
yea
radiant kraken
or
sharp geyser
it splits it based on whitespace iirc
radiant kraken
is it just the characters for the string
sharp geyser
tokens is just the operands and operators
it splits based on whitespace
and then I split them off into their own vectors
radiant kraken
so "2 3 +" -> '2', '3', '+'
radiant kraken
i see where that would work, not sure when you do 23 59 + tho
sharp geyser
I am not accounting for the fact that there will be more operands than operators
earnest phoenix
i see where that would work, not sure when you do `23 59 +` tho
It works the same, the extraction operator (>>) of std::istringstream only stops at a whitespace
earnest phoenix
It's undefined behavior
earnest phoenix
That's the proper way
radiant kraken
there we go
sharp geyser
Ah wait I realize now
earnest phoenix
I think you should prioritize setting up the debugger, it'll help you fix them much faster
radiant kraken
nah
sharp geyser
bruh
radiant kraken
it'll be better if we can get misty to make his calc app working
earnest phoenix
Funnily enough this is what it showed for the initial error, note the arguments
sharp geyser
Okay
changing tokens to std::string caused a lot of problems
and my brain is having issue solving em
earnest phoenix
bruh
You can use it through the command-line
Just lldb path/to/executable, and r (shortcut to process launch)
radiant kraken
for(const std::string& token : tokens) {
long operand = std::strtol(token.c_str(), &endPtr, 10);
if (*endPtr == '\0') {
operands.push_back(operand);
} else {
operators.push_back(token);
}
}
``` try thisyea that is what I was doing
but operators is a char vector
because I use a switch/case in the evaluate function to make my life easier when doing the math
radiant kraken
sharp geyser
yep
brain officially hurty
C++ is so strict with everything js would just be like "ok yep makes sense"
earnest phoenix
I'm a bit lost, can you show the current code and the behavior?
neon leaf
sharp geyser
radiant kraken
C++ is so strict with everything js would just be like "ok yep makes sense"
i'm in the middle of a math exam right now
sharp geyser
its having issues cause at L 59 operators is a char vector and I am trying to push a std::string
I am using chars for the operators because it makes no sense imo for it to be a std::string and it allows me to use a switch/case to do math evaluations easier
tho that might just be my brain being wonky
sharp geyser
1:11am
I usually sleep at 2am and wake up at 10am
perks of graduating
and having a job that is a closing shift
radiant kraken
sleep smh
earnest phoenix
its having issues cause at L 59 operators is a char vector and I am trying to pu...
Simply access the first character of the string when pushing the operator
It's a single char, nothing else
earnest phoenix
Those equations 
sharp geyser
Wait no
its doing 3 + 2 = 5 and then doing something with the remaining2
I guess adding it
but it should be multiplication
earnest phoenix
Just implement the ordinary syntax
earnest phoenix
sharp geyser
Okay now what the fuck is happening
the result is 8 now
OKAY WAIT
VOLTREX
I GOT IT
sharp geyser
@wheat mesa hey buddy I got it to work
radiant kraken
thru trial and error
radiant kraken
sharp geyser
I actually learned a lot here
Now I know how to convert a string to an int at least
radiant kraken
with the help of me 
sharp geyser
not only that I understand more on how vectors work
radiant kraken
poggers
sharp geyser
Ima move this code to another file
radiant kraken
wdym?
sharp geyser
he in my friends list
radiant kraken
damn i didnt know he accepts friends
sharp geyser
I was shocked he even accepted it
radiant kraken
lmao
proud light
Hi
radiant kraken
Turns out installing the dpp library is a process
or installing any other C++ library
good luck on that
sharp geyser
I got it installed, but doing the cmake stuff for it
Not ready for cmake
it is pain
so ima stick with projects that dont require a package for now
neon leaf
this took way longer than it shouldve https://fs.rjns.dev/v/uqTarusAqeGQRewOJM
whole knot
neon leaf
lyric mountain
https://tenor.com/view/do-not-run-python-python-computer-python-coding-coding-fu...
stiff dust
Hello, my bot is now have 7.5K servers its not count as very very big bot buts its big enough to create spam!
I need to check server language on all of commands or for example for any message sent on any server I need to check is that message.channel seted up as media only channel or not. so as a result of it I have to send a request to mongoDB to access to my Data Base and check it what should I do?
digital swan
cache db response with redis or something
lyric mountain
doesn't most reputable database libraries already cache data?
deft wolf
I think that if mongodb had a problem with handling a bot that is on 8,000 servers, it would not be such a popular database 
Of course, mySQL probably seems faster, but your database won't fall apart
lyric mountain
depends kinda, mongo will be faster for arbitrary data access, regular sql will be faster for structured data
stiff dust
I think that if mongodb had a problem with handling a bot that is on 8,000 serve...
I didnt say mongodb cant handle it
sharp geyser
int CheckingAccount::ChangeBalance(int new_balance) {
return this->balance = new_balance;
}
Would this return the value of balance after its set or would it return the old balance.
stiff dust
but I just dont want to request data all time
stiff dust
cache db response with redis or something
ok tnx
and also which one is better for sharding? own djs shardingManager or discord-hybrid-sharding?
sharp geyser
just use the djs sharding manager ngl
with how djs is now the hybrid sharding one is obsolete imo
Not to mention if you really wanted, you could just turn on auto sharding and call it a day.
stiff dust
so why many devs still use it? 
sharp geyser
If you want something easier though, you would wanna go with discord-hybrid-sharding
it has built in stuff to make it a little easier than just turning auto on
which uses your recommended shard count.
stiff dust
no I guess Im gonna try DJS Sharding
wheat mesa
```c++
int CheckingAccount::ChangeBalance(int new_balance) {
return this->ba...
iirc should return the new balance value
sharp geyser
iirc should return the new balance value
thanks
ALSO
didn't know if I told you
but I got the RPN thing to work
:D
wheat mesa
Nice!
sharp geyser
null and voltrex helped me in the end
wheat mesa
Good little exercise for learning how istringstream works too
sharp geyser
but I managed to figure out the general idea
Now I am working on a mock bank app
So I can learn about classes and headerfiles
wheat mesa
Always fun stuff
sharp geyser
yessir
wheat mesa
You should also learn about pointers and such sometime
Perhaps try implementing your own vector class (but without templates, just for ints or something)
sharp geyser
Im sure I can make use of them in this somehow
wheat mesa
That’ll be good for pointers
sharp geyser
Perhaps try implementing your own `vector` class (but without templates, just fo...
I can try
wheat mesa
That’ll teach you the basics of allocation and deallocation
sharp geyser
Isn't vector just a dynamic array
wheat mesa
Yes
sharp geyser
I'll try it out after this mock bank app
sour stream
deft wolf
Okey
neon leaf
its time 🙏
I finally got myself a proper pc
got it free actually
ordered a rtx 4060 for it
tulip ledge
ordered a rtx 4060 for it
Make sure not to bottleneck it with a bad cpu or power supply
sharp geyser
I dont remember how to check bottle necks
I think this is accurate
not terrible
I do want to eventually upgrade my cpu
just not sure what to
and if I do that, I might as well upgrade my mb as well so I can utilize ddr5 ram
stiff dust
Im sure I can make use of them in this somehow
I get 500MB more usage just in the start
sharp geyser
?
stiff dust
DJS Sharding is heavier
when I start my bot with Hybrid Sharding it takes 1GB ram
and now
with same amount of shards
it takes 1.5GB
sharp geyser
Damn I thought they made it better
stiff dust
as it start 8 different shard and everything work 8 times for example 8 ready.js but in hybrid it was only 2 ready.js as I had 2 Cluster and 4 shard in each cluster so there was same shard count but different usage
tulip ledge
i3 12th gen
i3 with a 4070? That’s definitely gonna bottleneck
You wont get full performance out of your gpu
sharp geyser
If you want clustering hybrid
unless you want to do it yourself with djs
I forgot djs has yet to implement such a thing
Which is surprising considering how much they hold bot dev's hands anyway
stiff dust
unless you want to do it yourself with djs
no I dont want to do it by my self
frosty gale
splendid
radiant kraken
So I can learn about classes and headerfiles
let me know if you have any questions
wheat mesa
Same C:
proven lantern
is there someway to check if a guild has a Premium App Subscription for my bot? I dont see it in the guild object.
https://discord.com/developers/docs/resources/guild#guild-object
heady quarry
Ah
proven lantern
is there someway to check if a guild has a `Premium App Subscription` for my bot...
proven lantern
if you respond with DEFERRED_CHANNEL_MESSAGE_WITH_SOURCE can you follow up with PREMIUM_REQUIRED?
https://discord.com/developers/docs/interactions/receiving-and-responding#interaction-response-object-interaction-callback-type
errant flax
can someone explain to me whats a normal? (in vector)
have googled the term still dont understand it
neon leaf
lyric mountain
can someone explain to me whats a normal? (in vector)
have googled the term stil...
Imagine you have many values with arbitrary values
Normalizing them is simply converting them to 0...1 range
Like 40, 100, 10 would become 0.4, 1, 0.1
sand knoll
earnest phoenix
@civic scroll @radiant kraken @sharp geyser was bored so made an entire pure parser for the calculator we were talking about
https://gist.github.com/VoltrexKeyva/b8e91900fb0daaaed799d28d3ea4ef6e
civic scroll
<@520964894279860224> <@661200758510977084> <@957347862314905610> was bored so m...
... on a phone
love are you out of your mind
civic scroll
but why must he torture himself like that
sharp geyser
<@520964894279860224> <@661200758510977084> <@957347862314905610> was bored so m...
What in the fuck
Almost 800 lines on a phone
Buddy, thats not just being bored
earnest phoenix
Dedication
sharp geyser
Also just want to point out
I never would of been able to do something like that with my current knowledge
civic scroll
@earnest phoenix @radiant kraken sayulang 
oh shit to is supposed to be a keyword
fixed
radiant kraken
<@456226577798135808> <@661200758510977084> sayulang <:gx_tro:826400177878466580...
how did u work on the vscode syntax highlighting
civic scroll
what's that
syntax highlighting engine for vscode i think
earnest phoenix
I never would of been able to do something like that with my current knowledge
What I made is a pure recursive descent parser, one of the hardest and most capable parsers out there (used in basically every mainstream programming language implementation)
What I was suggesting to you wasn't that, there are many many types of parsers that are much simpler but not as powerful or flexible
wheat mesa
It looks pretty close to what I made in C#
Granted I based it off of the crafting interpreters implementation
earnest phoenix
It looks pretty close to what I made in C#
Show 👀
wheat mesa
This was one of the first projects I did when I was getting into parsing, pretty proud of adding the whole “MathLibrary.cs” file to it, it feels easy to use and extensible
earnest phoenix
https://github.com/Jwaffled/MathExpressionParsing
That's pretty nice
As much as I like the visitor pattern, it's incredibly hard to implement in programming languages that have extremely strict type systems like C/C++ and Rust
wheat mesa
Yeah
It’s really annoying, which is why I much prefer rust’s type system for interpreters and such
Versatile pattern matching + a flexible type system for representing recursive structures = a beautiful interpreter
Here’s the same thing implemented in rust (without functions) https://github.com/Jwaffled/math_parser_rs
eternal osprey
hey guys i have written my own algorithm for a school project where we had to return the minimal amount of boxes by fitting each and one other
anyways
i ran my code through an online "chat gpt detector"... it returned me fucking 55%
i didn't even copy code from chatgpt, only asked questions about what some issues were and how to fix them lmao
earnest phoenix
Here’s the same thing implemented in rust (without functions) https://github.com...
That's awesome
Btw what's the 10 here supposed to be?
https://github.com/Jwaffled/math_parser_rs/blob/master/src/scanner.rs#L114
neon leaf
i ran my code through an online "chat gpt detector"... it returned me fucking 55...
as long as your can explain ur code it doesnt really matter
eternal osprey
my university really bitches on that type of stuff
but the thing is, i literally coded everything myself
so why the fuck is chatgpt zero highlighting me as 54% ai generated?
the stuff it highlighted are really strange as well, such as importing packages, variable names, function signatures..?
earnest phoenix
ChatGPT Zero is really bad at detecting AI vs hand-written code
neon leaf
because code doesnt have as much possible variation as normal text
eternal osprey
i see, i hope that my school isn't using that then..
they are probably using moss of stanford
heard it's a good one
gray mauve
h
wheat mesa
Btw what's the `10` here supposed to be?
<https://github.com/Jwaffled/math_parse...
It’s the radix of the character, for some reason there’s no overload that assumes it’s base 10, so I have to specify that I’m parsing a base 10 number
earnest phoenix
Oh, yeah I would assume that there would be a default base 10 radix as well
wheat mesa
Or maybe there is a version that assumes base 10 and I just didn’t see it when I wrote that
neon leaf
I hate this https://fs.rjns.dev/v/rlzuCGNuyqiQfJnVWy
sharp geyser
I hate this more
Looks fun to me
neon leaf
yea especially the part where it takes 3 hours
wheat mesa
Does anyone have recommendations on how to efficiently store and process objects in a physics simulation? Last time I used an ECS, but I felt like I had difficulty achieving flexible behavior
Not sure if I should go after that again, or if I should try some other structure
eternal osprey
hey guys
has anyone any recommendations on how to make this look better
idk the products are looking dookie for some reason but i can't place it.
sharp verge
has anyone any recommendations on how to make this look better
Usually it's better not to center the text, left align is cleaner and easier to look at/follow.
To me the images feel a little too wide?
You could also consider adding a container with a box shadow around each product
eternal osprey
i see, thank you for the help!
deft wolf
Actually, wouldn't it be better to move this black stripe with stars to the footer? It's probably a matter of taste, but I feel strange when there is a number of stars in the upper right corner, the footer seems to me a better place for such information than the very top of the page
rocky wave
How do i add the feature of sending voice messages to my discord bot
Like just send an mp3 file as voice message
pale vessel
the search bar is too short
its average
radiant kraken
i mean it's okay if it's for the mobile version but
imo it needs to be a bit wider
eternal osprey
hey java gurus, i have a question:
I am creating an algorithm to return the minimal amount of boxes needed. One box can fit in another box based on permutations. So suppose a box has dimensions [x,y,z], then you must check all permutations of the box as:
A box fits if there exists a permutation such that x > x of other box, y > y of other box, z > z of other box.
Right now this is my output of my FIRST box splitter:
[[[0.747756, 0.642319, 0.569011], [0.514339, 0.583412, 0.660649]], [[0.556423, 0.772266, 0.755868], [0.675496, 0.705229, 0.544096]], [[0.678271, 0.663318, 0.571389]], [[0.842022, 0.73891, 0.698524], [0.622235, 0.8074, 0.632252], [0.673077, 0.708456, 0.570999], [0.757113, 0.634282, 0.610887]], [[0.605403, 0.879344, 0.840328]], [[0.796699, 0.95473, 0.81393], [0.579564, 0.879689, 0.736052], [0.571137, 0.532766, 0.936874], [0.932276, 0.591703, 0.658759], [0.945931, 0.652785, 0.737563], [0.88937, 0.538176, 0.534113]], [[0.871447, 0.690473, 0.88035]], [[0.777473, 0.892142, 0.962822], [0.579407, 0.848634, 0.925978]], [[0.803432, 0.860415, 0.956237]]]
However, in my recursive call it goes horribly wrong:
public static void boxFitter() {
boolean hasChanged = false;
for(int i = 0; i < boxPartitions.size(); i++){
for(int j = 0; j < boxPartitions.size(); j++){
if(isSmaller(boxPartitions.get(i).get(0), boxPartitions.get(j).get(0))){
boxPartitions.get(i).addAll(boxPartitions.get(j));
result.add(boxPartitions.get(i));
boxPartitions.remove(boxPartitions.get(i));
boxPartitions.remove(boxPartitions.get(j));
i= 0;
j= 0;
hasChanged = true;
}
}
}
if(boxPartitions.size() > 1 && hasChanged){
boxFitter();
}else if(boxPartitions.size() == 1 && hasChanged){
Vector<Double> toCheck = boxPartitions.get(0).get(0);
for(int i = 0; i < result.size(); i++){
if(isSmaller(result.get(i).get(0), toCheck)){
result.get(i).addAll(boxPartitions.get(0));
boxPartitions.remove(boxPartitions.get(0));
} else if(boxPartitions.size() == 1 && isSmaller(toCheck, result.get(i).get(0))){
result.get(i).addAll(0, boxPartitions.get(0));
boxPartitions.remove(boxPartitions.get(0));
}
}
}
}```it returns me fucking 4 instead of 9 for the minimal boxes. i just need any help on how to progress further and if someone sees the issue..
lyric mountain
I...have no idea of what you asked
but a thing is for sure, you need to optimize those accesses
sage bobcat
but a thing is for sure, you need to optimize those accesses
One message removed from a suspended account.
eternal osprey
I...have no idea of what you asked
We get a vector of boxes as inputs
They want you to fit boxes inside each other if they fit, meaning that there’s a permutation of the 2 boxes where the dimensions of one box are all bigger than the other.
But for some reason the above method isn’t really doing the job correctly. It partitions the boxes the wrong way
sharp geyser
@wheat mesa when it comes to making my own vector implementation, how do you advise I start off?
My thought process is a bit flawed
sharp geyser
@earnest phoenix what’s your thoughts on this? I want to try and implement my own vector class, but only supporting ints. Waffle said it’d help with learning pointers and references as well as allocation and deallocation
I just simply don’t know where to start. I was going to treat it like a dynamic array that can take an endless amount of values but I don’t know how to achieve this without actually using vector itself.
Which defeats the purpose if I use the built in vector
I know arrays work by doing type[size] but I don’t know how I’d make that dynamic
frosty gale
usually whats done is you allocate x amounts of ints in your case as an array with an allocator to start off with so you have a plain c array to work with
frosty gale
I know arrays work by doing `type[size]` but I don’t know how I’d make that dyna...
idk what language youre using but you can make that dynamic aka allocate it using an allocator then deallocate that array once you dont need it anymore with new so something like int* array = new int[x]; in c++ which makes an array of size x
then array references the start of the first int so you can set data on it at specific indexes as usual
theres no boundary checks tho thats for you to implement in a custom vector
or you can simply use a c++ array (std::array) which is a bit more intuitive and safer to work with to make the array 🤷♂️
sharp geyser
I see
Yea I’m quite new to c++ so allocation and deallocation are foggy subjects for me
sharp geyser
idk what language youre using but you can make that dynamic aka allocate it usin...
Would x be something that has to be provided when using the custom vector class or would it be any number?
frosty gale
you can make the user provide the initial size of the internal array but whats usually done is c++ starts with some number (it can be anything) as the initial size for the vector array and then grows it once more elements are inserted
you should focus on setting/deleting/initiating the vector first though leave growing/shrinking the internal array for last
sharp geyser
So it has a default size but its size can be modified depending on what’s allocated to the array?
frosty gale
essentially yeah
the initial size is usually something that balances the performance of inserting the first few elements and not having too excessively big of an array for no reason
sharp geyser
Makes sense
frosty gale
but it really doesnt matter too much can be something on the top of your head like 5 or something or whatever you like
sharp geyser
Yea in reality it just needs to be something to start the vector off with
Well thanks a lot for your advice
I’ll try and see if I can get something started
frosty gale
yeah try keep it stupid simple at first so you dont get too ambitious without knowing how to do certain stuff
one thing at a time!!
earnest phoenix
I know arrays work by doing `type[size]` but I don’t know how I’d make that dyna...
You implement a capacity and a tracker of vector size, always start with a capacity of one, and allocate an array of the given type with a size of 1
Every time you reach the capacity you basically allocate a new array and move the elements of the previous array to the new one, deallocate the old one, and use the newly allocated array, and increase the capacity on a scale of power of 2
Pretty much every compiler that implements vectors does this
radiant kraken
@sharp geyser ```cpp
const int size_of_each_element = sizeof(int);
int * pointer = (int *)std::malloc(initial_capacity * size_of_each_element);
// pointer[0], pointer[1], etc...
if (pointer == nullptr) {
// system out of memory
}
// resize the vector to a new capacity
pointer = std::realloc(pointer, new_capacity * size_of_each_element);
// deletes/frees the memory back to the OS. this MUST be called once you're done with the vector, otherwise you have a memory leak
std::free(pointer);
I see
Ima try and implement something similar tomorrow later today after I wake up
Since its my day off
radiant kraken
sharp geyser
I wasn't too sure how to free the block of memeory
earnest phoenix
<@957347862314905610> ```cpp
const int size_of_each_element = sizeof(int);
int *...
I'd recommend not calling std::malloc() and then check if it failed, just implement a capacity check instead
sharp geyser
but then I remembered there was delete keyword
earnest phoenix
Because std::malloc() has a much higher overhead than just a simple check
sharp geyser
what is the difference between using malloc and just new
radiant kraken
what is the difference between using malloc and just ``new``
new automatically checks if the pointer is nullptr or not for you
both basically does the same thing
sharp geyser
so is it better to use new over malloc?
radiant kraken
no imo
sharp geyser
or for learning purpose is it better to use malloc
earnest phoenix
new calls the constructor where malloc() does not
radiant kraken
^ new is good for classes
sharp geyser
so with malloc i'd have to do a lot more checks myself.
sharp geyser
right right
radiant kraken
I'd recommend not calling `std::malloc()` and then check if it failed, just impl...
wdym
if you're using raw C structs (without constructors) or primitive types (pointers, ints, chars, etc) go for std::malloc, otherwise if you're going for classes/structs with constructors go for new
sharp geyser
So when implementing my own custom class, it entails a headerfile as well. I am still not used to what to do in those. I know I should be outlining what is included int he cpp file but when it comes to outlining what a class is I am clueless.
radiant kraken
so are you working on a library of some sort
sharp geyser
Not really
radiant kraken
e.g you want to keep things in separate C++ files
earnest phoenix
wdym
std::malloc() has multiple steps and branches that it goes through before bailing out and returning a nullptr indicating failure, whereas you can know ahead of time that it goes beyond the capacity so you can optimize it further with a simple capacity check
sharp geyser
Just messing around in c++ and waffle recommended to make a vector implementation
radiant kraken
ah
sharp geyser
so I thought i'd just make it a class so I can mess with headerfiles as well
radiant kraken
then since you're still a beginner then i recommend write the class definition in a C++ header file
sharp geyser
wdym? Isn't that what I was asking about
earnest phoenix
You basically just only write the types of what the class contains (declaration), not the bodies (definition)
radiant kraken
that should be for later imo, linking can get a bit complicated for a beginner
unless his IDE got his back or something
radiant kraken
voltrex writing a long essay 
sharp geyser
He on phone
earnest phoenix
Example:
foo.h:
#ifndef FOO_H
#define FOO_H
class Foo {
public:
int foo;
Foo(int foo);
int bar(int baz);
};
#endif // FOO_H
foo.cpp
#include "foo.h"
Foo::Foo(int foo) : foo(foo) {}
int Foo::bar(int baz) const { return foo + baz; }
not main.cpp
foo.cpp
main.cpp should be for the main function/program startup/shutdown
earnest phoenix
Did you look at the bottom?
It's an example, but yes it should be separated
There
radiant kraken
also, why not ```cpp
#include "foo.h"
Foo::Foo(int foo): foo(foo) {}
int Foo::bar(int baz) { return foo + baz; }
i've seen some examples do this
earnest phoenix
Yes that is correct way actually
earnest phoenix
Pretty much every compiler that implements vectors does this
radiant kraken
<:troll:860981543555563541>
https://github.com/llvm/llvm-project/blob/main/libc...
not as blazingly fast as Rust's Vec tho
sharp geyser
@earnest phoenix @radiant kraken so what does int* array; do?
I notice that when messing with it in code, it seems to create a one dimensional list/array/something
as I can do array[1] and assign stuff to it
but I am not sure if I am mistaken
radiant kraken
<@456226577798135808> <@661200758510977084> so what does ``int* array;`` do?
wdym?
sharp geyser
I don't know how to really explain it any better
I simply don't understand what int* array is.
like int array obviously means that array will hold a number
radiant kraken
yes
sharp geyser
but adding an asterisk and what the end behaviour is I don't know
I guess thats as simple as I can get my question
radiant kraken
int * array is a pointer to an int in memory
sharp geyser
I see
radiant kraken
If you think about it arrays in C/C++ are just pointers to the first element
array[1] is the memory address array + index * the size of each element in array, in this case sizeof(int)
sharp geyser
I am just trying to figure out the best method of holding onto the array once its been allocated
earnest phoenix
<@456226577798135808> <@661200758510977084> so what does ``int* array;`` do?
It creates a pointer to an int, the * in types denotes a pointer, meanwhile in body it denotes deferencing a pointer (accessing its value), if you read the declaration from right-to-left, it is a * (pointer) to int
Pointers are the addresses of values separated by value size in memory, which can be assigned either the value itself or an array of it
int* p can hold either an integer or an array of integers, but when the latter, it'll decay to the first element of the array, and you can access the others using the subscript operator ([]) or by pointer arithmetic (p++ = shift by sizeof(int))
However, int (*p)[5] is a pointer to a whole array of 5 integers (not just the first element), so it can't hold just an integer, and doing pointer arithmetic on an this will shift the array by sizeof(int) * 5
sharp geyser
I see
radiant kraken
I am just trying to figure out the best method of holding onto the array once it...
int *
int thing[] is only for array literals
not dynamic arrays
earnest phoenix
^
radiant kraken
volt u dont really need long essays for everything
earnest phoenix
I do for explaining things in detail
sharp geyser
So for my vector implementation I want to have an internal array correct? So would in my headerfile would I do something along the lines of
class {
private:
int* array;
public:
Vector();
}
Vector::Vector(){
this->array = new int[1]
}
or something along these lines
radiant kraken
it's better to explain things in simpler terms
radiant kraken
So for my vector implementation I want to have an internal array correct? So wou...
new int[initial_capacity]; yes
earnest phoenix
I'm explaining it in simpler terms in more detail
sharp geyser
new int[initial_capacity]; yes
well the initial capacity would be 1
and with each new element the capcity changes as a new array is made
radiant kraken
sure
radiant kraken
It creates a pointer to an int, the `*` in types denotes a pointer, meanwhile in...
i've never seen someone use int (*p)[5] before
earnest phoenix
Make a capacity field that keeps track of the capacity so you can easily check it on push
radiant kraken
ngl sounds like a useless feature
radiant kraken
Make a `capacity` field that keeps track of the capacity so you can easily check...
Don't forget a length field, for the current amount of populated elements in the array
eternal osprey
public static void createBoxPartitions() {
while (!inputBoxes.isEmpty()) {
Vector<Vector<Double>> currentBox = new Vector<>();
Vector<Double> firstBox = inputBoxes.remove(0);
currentBox.add(firstBox);
for (int i = 0; i < inputBoxes.size(); i++) {
if (isSmaller(firstBox, inputBoxes.get(i))) {
currentBox.add(inputBoxes.get(i));
inputBoxes.remove(i);
i = 0;
} else if (isSmaller(inputBoxes.get(i), firstBox)) {
currentBox.add(0, inputBoxes.get(i));
inputBoxes.remove(i);
i = 0;
} else {
Vector<Vector<Double>> distinctBox = new Vector<>();
distinctBox.add(inputBoxes.get(i));
inputBoxes.remove(i);
boxPartitions.add(distinctBox);
i = 0;
}
}
}
}
For some reason my algorithm partitions all boxes in 4 boxes rather than 6. Would anyone know why?
eternal osprey
This is the isSmaller function:
public static boolean isSmaller(Vector<Double> largerBox, Vector<Double> smallerBox) {
Vector<Double> sortedLargerBox = new Vector<>(largerBox);
Vector<Double> sortedSmallerBox = new Vector<>(smallerBox);
Collections.sort(sortedLargerBox);
Collections.sort(sortedSmallerBox);
for (int i = 0; i < 3; i++) {
if (sortedLargerBox.get(i) <= sortedSmallerBox.get(i)) {
return false;
}
}
return true;
}```Who doesn't like getting the size of the internal array each time you need the size of it
sharp geyser
idk man im tired
radiant kraken
you cant
sharp geyser
its 3am
radiant kraken
go to bed then
sharp geyser
because its impossible to determine without one
Where there is a will there is a way
radiant kraken
gl finding a way
earnest phoenix
i've never seen someone use int (*p)[5] before
It's a way to let the compiler enforce the size of array that the pointer is pointing at, a plain array or pointer does not hold its size information across function passes so the compiler cannot enforce it
sharp geyser
int* Vector::insert(int element, int index = 0) {
int* temp = this->array;
this->capacity += 1;
for(int i = this->length; i >= index; i--) {
temp[i] = temp[i - 1];
}
temp[index - 1] = element;
int* newArray = new int[this->capacity];
newArray = temp;
delete this->array;
this->array = newArray;
return this->array;
}
Okay this is my shitty implementation of inserting an element into the vector at a specific index.
Please tell me I am at least close
😩
radiant kraken
because its much more efficient and faster
and doesnt have to delete and make a new array
sharp geyser
I see
earnest phoenix
i need a real world example
Enforcing good memory management practice
#include <cstring>
void print_p(int* arr) { // no size information
}
void print_a(
int arr[5]) { // the `[5]` is redundant here and is not enforced as the
// array decays to a pointer, losing size information
}
void print_pa(int (*p)[5]) { // size information is not lost
}
int main() {
int* p = new int[10];
memset(p, 0, 10 * sizeof(int));
print_p(p); // OK, unexpected
int a[10];
memset(a, 0, 10 * sizeof(int));
print_a(a); // OK, unexpected
int(*pa)[10] = &a;
print_pa(pa); // compiler error, expected
}
People do, a lot actually
radiant kraken
where?
earnest phoenix
I'm not gonna go through lots of repositories to find where exactly they are used but they're used in critical places, such as mission-critical projects
radiant kraken
mission-critical?
sharp geyser
Okay so wait
I would use realloc to change the size of this->array and then I would then change what this->array is
earnest phoenix
mission-critical?
sharp geyser
I am just basing this off of reading cppreference
int* newArray = (int*) std::realloc(this->array, this->capacity);
if(newArray != nullptr){
this->array = temp;
}
so something like this
radiant kraken
I would use realloc to change the size of ``this->array`` and then I would then ...
well you just assign that to this->array
radiant kraken
```cpp
int* newArray = (int*) std::realloc(this->array, this->capacity);
...
exactly
sharp geyser
So I ended up doing it correctly
Now next question
actually no
let me test first
before asking
sharp geyser
I gotta try and learn
so I wont ask a question until I am truly stuck
Though actually I do have a question
does c++ have the concept of optional arguments
radiant kraken
yes
sharp geyser
Cause I notice despite giving index a default of 0
radiant kraken
look up std::optional<thing>
sharp geyser
when using said method it still expects 2 arguments
Ah
Gotcha
thanks <3
now to truly test
radiant kraken
<3
@sharp geyser oh besides did you know something about ```cpp
Class::Class() {
// size zero
}
Class::Class(int size) {
// with size
}
afaik that is also possible
sharp geyser
Wait what
radiant kraken
@earnest phoenix afaik there's default constructors and all that, what are they for?
sharp geyser
Oh right just realized something
I can't treat this like it is an array
as its a class
I just tried doing vec[0]
earnest phoenix
Both C and C++ have it
sharp geyser
so I could technically make it so they can supply a size themselves?
radiant kraken
C does not have operator overloading???
radiant kraken
so I could technically make it so they can supply a size themselves?
afaik it's ```cpp
int Class::operator[](int index) {
}
There's the default constructor and destructor, copy constructor and copy assignment, move constructor and move assignment
sharp geyser
Vector::Vector() {
this->capacity = 1;
this->array = new int[1];
this->length = 1;
}
Vector::Vector(int size) {
this-> capacity = size;
this-> array = new int[size];
this-> length = size;
}
yuhh
sharp geyser
Okay
So another thing
Is there anyway I can make Vector vec; be treated like an array
so once I make a new vec instance
I can do vec.insert(199) -> vec[0]
to get the first element
radiant kraken
afaik it's ```cpp
int Class::operator[](int index) {
}
``` or something like th...
this
earnest phoenix
C does not have operator overloading???
Overloading in C can be achieved using C11 _Generic, but yeah it doesn't built-in support for it
radiant kraken
oh if you want for the values to be modifiable, return a int &, (int reference)
radiant kraken
oh if you want for the values to be modifiable, return a `int &`, (int reference...
@earnest phoenix how is this possible, afaik pointer to reference is impossible in C++
sharp geyser
its for operator overloading
I don't quite get it
radiant kraken
which part do u dont get?
sharp geyser
How it is supposed to work
civic scroll
How it is supposed to work
array[3]
void Vec::operator [] (int index) {
index // 3
}
sis this is not rust
civic scroll
wait whay
earnest phoenix
<@456226577798135808> how is this possible, afaik pointer to reference is imposs...
What you suggest is only possible with global variables, pointer to reference is indeed invalid
civic scroll
pointer + offset
radiant kraken
array is a vector class
earnest phoenix
how is `array[thing] = 69;` possible
Hm?
radiant kraken
oh wait
civic scroll
it's still continuous memory reason
radiant kraken
is it just void Vec::operator[](int index, int value) {} ?
civic scroll
nope
civic scroll
in this case it would be a pointer deref
sharp geyser
// in Vector.h
int operator[](int index) const;
//in Vector.cpp
int Vector::operator[](int index) const {
return this->array[index];
}
so something like this?
radiant kraken
yes
sharp geyser
my IDE pushed the const onto it
radiant kraken
thats good
sharp geyser
I assume I don't want it modifiable
civic scroll
```c++
// in Vector.h
int operator[](int index) const;
//in Vector.cpp
int Vecto...
but why would you not declare the method inside the class?
radiant kraken
because it detects that ur function does not modify the class's properties
sharp geyser
but why would you not declare the method inside the class?
Wdym
radiant kraken
but why would you not declare the method inside the class?
so he can write one in a separate C++ file?
it's the convention if you don't want to create a single-header library
civic scroll
Wdym
like
class Vector {
public:
int operator [] (int index) const { ... }
}
in the cpp side
radiant kraken
that's if you want to make a header-only library
civic scroll
wym?
earnest phoenix
is it just `void Vec::operator[](int index, int value) {}` ?
radiant kraken
the convention is to separate the class definition and the class method bodies
civic scroll
it also has the implementation there, how come it only generates headers
sharp geyser
In file included from C:/Dev/Vector/main.cpp:2:
C:/Dev/Vector/Vector.h:19:32: error: no template named 'optional' in namespace 'std'
19 | int* insert(int element, std::optional<int> index);
civic scroll
can i just use something else to automatically generate headeds from my class
radiant kraken
#include <optional>
earnest phoenix
```
In file included from C:/Dev/Vector/main.cpp:2:
C:/Dev/Vector/Vector.h:19:32...
You need to include the <optional> header
sharp geyser
I did
civic scroll
L
rust has that built-in
smh
civic scroll
wait...
sharp geyser
lol
civic scroll
you didn't do any checks for array accessing?
sharp geyser
Go for it
radiant kraken
if (index >= this->length) { yeet }
radiant kraken
insane i know
earnest phoenix
and it asks me to include header optional
What C++ version are you using?
earnest phoenix
std::optional requires C++17 or higher
civic scroll
what ide you in
sharp geyser
I think c++ 20
civic scroll
you think?
sharp geyser
Well tbh sayu
radiant kraken
he's in CLion
sharp geyser
CLion
civic scroll
open settings
sharp geyser
it standard was set to C++ 20