Can't iterate through std::map [closed] - c++

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Since I've started to using std::map I've started to receive assertion error whenever I click on the button. I want to clear all the contents inside my_map and start adding again everytime I click the button.
my.cpp
typedef std::map<str, MyClass> mapper;
mapper my_map;
void add_map(const str& name, MyClass* l) { /...../ }
void invoke_me()
{
Here I initialized variable i with the size of my_map, however, it returns the previous size before it was cleared
int i = my_map.size(); // i = 4, my_map.size() = 1
if (!my_map.empty())
{
for (const auto& it : map)
{
// Assert error: map/set iterator not incrementable
const MyClass& l = it.second;
l.on_clicked();
}
}
}
// cont'd
This should do the neat clearing of my_map, but I don't think it's doing the right job
void clear_map()
{
my_map.clear();
}
implementor.h
struct MyClass
{
std::function<void()> on_clicked;
};
implementor.cpp
MyClass button;
button.on_clicked = [&] {
clear_map();
add_map("MyButton", &button);
};
Well actually on_click is a callback, and it has to be called through the invoke_me function
main.cpp
while (RUNNING)
invoke_me();
I would say that it is because of incorrect map size that's why the it keeps looping even if it's out of bounds, or maybe I'd corrupted or messed up that map.

Answer 1

There might be more issues, but this looks to be the main one:
button.on_clicked = [&] {
clear_map();
add_map("MyButton", &button);
};
You're clearing the map, and this function gets called while you're iterating:
for (const auto& it : my_map)
{
// Assert error: map/set iterator not incrementable
const MyClass& l = it.second;
l.on_clicked();
}
Your iterators are being invalidated by the clear.