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What is the performance cost of having a virtual method in a C++ class?
... be non-virtual is an abominable policy.
– underscore_d
May 20 '17 at 19:34
add a comment
...
How can I use an array of function pointers?
...ointers.
void fun1()
{
}
void fun2()
{
}
void fun3()
{
}
void (*func_ptr[3])() = {fun1, fun2, fun3};
main()
{
int option;
printf("\nEnter function number you want");
printf("\nYou should not enter other than 0 , 1, 2"); /* because we have only 3 functions */
scanf("%d",&...
LEN function not including trailing spaces in SQL Server
...
I would use LEN(REPLACE(expr, ' ', '_')). This should work with varchar and nvarchar and strings containing special unicode control characters.
– Olivier Jacot-Descombes
Apr 24 '14 at 16:01
...
Using the Android Application class to persist data
...nController extends Application {
private static ApplicationController _appCtrl;
public static ApplicationController getAppCtrl()
{
return _appCtrl;
}
}
Because subclasses of Application also can obtain the Resources, you could access them simply when you define a static ...
Setting PATH environment variable in OSX permanently
...is the only solution that works on El Capitan. Better than modifying .bash_profile and .profile.
– IgorGanapolsky
Nov 29 '15 at 21:06
1
...
How can I quickly delete a line in VIM starting at the cursor position?
...atever was yanked before.
The true delete command in the OP's context is "_D (or "_C if insert mode is desired) This sends the deleted content into the black hole register, designated by "_, where it will bother no one ever again (although you can still undo this action using u).
That being said,...
NGINX to reverse proxy websockets AND enable SSL (wss://)?
...s on the release 1.3.13. Example of use:
location /websocket/ {
proxy_pass http://backend_host;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
proxy_read_timeout 86400;
}
You can also check the nginx changelog and th...
How does lucene index documents?
...robably the best more recent alternative is http://lucene.apache.org/core/3_6_2/fileformats.html
There's an even more recent version at http://lucene.apache.org/core/4_10_2/core/org/apache/lucene/codecs/lucene410/package-summary.html#package_description, but it seems to have less information in it ...
Mercurial .hgignore for Visual Studio 2010 projects
...lob syntax
syntax: glob
*.obj
*.pdb
*.user
*.aps
*.pch
*.vspscc
*.vssscc
*_i.c
*_p.c
*.ncb
*.suo
*.tlb
*.tlh
*.bak
*.[Cc]ache
*.ilk
*.log
*.lib
*.sbr
*.scc
*.DotSettings
[Bb]in
[Dd]ebug*/**
obj/
[Rr]elease*/**
_ReSharper*/**
NDependOut/**
packages/**
[Tt]humbs.db
[Tt]est[Rr]esult*
[Bb]uild[Ll]og.*
...
Why are dates calculated from January 1st, 1970?
...
Astronomers use their own epochal date: http://en.wikipedia.org/wiki/Epoch_(astronomy)
Why? A date has to be chosen to make the math work out. Any random date will work.
A date far in the past avoids negative numbers for the general case.
Some of the smarter packages use the proleptic Gregoria...