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Is there a way to instantiate objects from a string holding their class name?
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Nope, there is none, unless you do the mapping yourself. C++ has no mechanism to create objects whose types are determined at runtime. You can use a map to do that mapping yourself, though:
template<typename T> Base * createInstance() { return new T; }
typedef std::map<s...
C++ Double Address Operator? (&&)
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This is C++11 code. In C++11, the && token can be used to mean an "rvalue reference".
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How to printf uint64_t? Fails with: “spurious trailing ‘%’ in format”
... suffice. The __STDC_FORMAT_MACROS macro is only required for inclusion in C++.
– Jens Gustedt
Nov 15 '11 at 8:05
15
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C++ Convert string (or char*) to wstring (or wchar_t*)
...interest, then your problem can be fully solved with the standard library (C++11 and newer) alone.
The TL;DR version:
#include <locale>
#include <codecvt>
#include <string>
std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> converter;
std::string narrow = convert...
ACE vs Boost vs POCO [closed]
I have been working with the Boost C++ Libraries for quite some time. I absolutely love the Boost Asio C++ library for network programming. However I was introduced to two other libraries: POCO and Adaptive Communication Environment (ACE) framework . I would like to know the good and bad of ...
What is the difference between LR, SLR, and LALR parsers?
... This matters a lot when trying to deal to non-academic langauges such as C++ or Fortran, where you literally needs thousands of rules to handle the entire language well, and you don't want to spend your life trying to hack the grammar rules to meet the limitations of LALR (or even LR).
As a sort ...
How do I handle the window close event in Tkinter?
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root.protocol("WM_DELETE_WINDOW", close_window)
cv = Canvas(root, width=200, height=200)
cv.pack()
running = True;
# This is an endless loop stopped only by setting 'running' to 'False'
while running:
for i in range(200):
if not running:
break
cv.create_oval(i, i, i+1, i+1)
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round() for float in C++
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It's available since C++11 in cmath (according to http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3337.pdf)
#include <cmath>
#include <iostream>
int main(int argc, char** argv) {
std::cout << "round(0.5):\t" <<...
Google MAP API Uncaught TypeError: Cannot read property 'offsetWidth' of null
...ake sure the CSS has code to style your particular map e.g. #map1 { width: 200px; height: 200px; } or similar so it renders.
– Tahir Khalid
Jul 28 '16 at 3:04
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Checking for NULL pointer in C/C++ [closed]
...inct.
Edit: As SoapBox points out in a comment, they are compatible with C++ classes such as auto_ptr that are objects that act as pointers and which provide a conversion to bool to enable exactly this idiom. For these objects, an explicit comparison to NULL would have to invoke a conversion to po...