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Why do we need a pure virtual destructor in C++?
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Probably the real reason that pure virtual destructors are allowed is that to prohibit them would mean adding another rule to the language and there's no need for this rule since no ill-effects can come from allowing a pure virtual destructor.
Nope, plain old virtual is enough.
If...
How can I add a help method to a shell script?
... into a shell script? I would like to display a help message when a user calls myscript.sh -h .
6 Answers
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What is the Oracle equivalent of SQL Server's IsNull() function?
In SQL Server we can type IsNull() to determine if a field is null. Is there an equivalent function in PL/SQL?
4 Answers...
How to check if command line tools is installed
I have a macbook pro with OS X 10.8.2.
XCode is installed. I know this as it appears in the Applications directory.
There are also the xcodebuild and xcode-select files in /usr/bin
I need to know if the command line tools is installed.
Is there a command for it?
What can I do to see if XCode CLT is ...
Is it possible to send a variable number of arguments to a JavaScript function?
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Update: Since ES6, you can simply use the spread syntax when calling the function:
func(...arr);
Since ES6 also if you expect to treat your arguments as an array, you can also use the spread syntax in the parameter list, for example:
function func(...args) {
args.forEach(arg =>...
ReSharper - force curly braces around single line
...t to add the braces in the single-line scenario. And I had to set that in all six dropdowns under "Force Braces" to catch all the scenarios:
What I was really hoping for was to be able to set up ReSharper to do a yellow warning or red error when the rule was violated, but I haven't found a way t...
Storing Image Data for offline web application (client-side storage database)
...; FF for Android
Fetch from web server
using XHR2 (supported on almost all browsers) for blob download from web server
I went with XHR2-Lib by Phil Parsons, which is very much like JQUERY .ajax()
https://github.com/p-m-p/xhr2-lib
Storage
IndexedDB for IE and FireFox
Chrome: Polyfill (blo...
What are Maven goals and phases and what is their difference?
...can specify a goal or a phase. If you specify a phase then maven will run all phases up to the phase you specified in order (e.g. if you specify package it will first run through the compile phase and then the test phase and finally the package phase) and for each phase it will run all goals attach...
Python: List vs Dict for look up table
...the hash table, only pointers, i.e. hou have 40M for the ints (well, not really when a lot of them are small) and 60M for the hash table. I agree that it's not that much of a problem nowadays, still it's worthwhile to keep in mind.
– Torsten Marek
Feb 5 '09 at ...
Get a UTC timestamp [duplicate]
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thanks for the clarifications Aprillion! Finally I understand why people keep saying new Date().getTime() or Date.now() is UTC but when I try console.log(new Date()), it displays time in my timezone. The Date internally has the timestamp (milliseconds) in UTC (w/c is w...