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To ARC or not to ARC? What are the pros and cons? [closed]
...ge collection. It has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables, inline functions, etc.)...
PowerShell says “execution of scripts is disabled on this system.”
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If you're using Windows Server 2008 R2 then there is an x64 and x86 version of PowerShell both of which have to have their execution policies set. Did you set the execution policy on both hosts?
As an Administrator, you can set the execution policy by typing this into your PowerShell...
Can a CSS class inherit one or more other classes?
I feel dumb for having been a web programmer for so long and not knowing the answer to this question, I actually hope it's possible and I just didn't know about rather than what I think is the answer (which is that it's not possible).
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Running script upon login mac [closed]
... earned a "Good answer" badge for this answer. While my solution is simple and working, the cleanest way to run any program or shell script at login time is described in @trisweb's answer, unless, you want interactivity.
With automator solution you can do things like next:
so, asking to run a scr...
Rails new vs create
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Within Rails' implementation of REST new and create are treated differently.
An HTTP GET to /resources/new is intended to render a form suitable for creating a new resource, which it does by calling the new action within the controller, which creates a new unsaved...
Docker - a way to give access to a host USB or serial device?
...in /dev/bus/usb, you can mount this in the container using privileged mode and the volumes option. For example:
docker run -t -i --privileged -v /dev/bus/usb:/dev/bus/usb ubuntu bash
Note that as the name implies, --privileged is insecure and should be handled with care.
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Should I instantiate instance variables on declaration or in the constructor?
...he compiler.
The first variant is more readable.
You can't have exception handling with the first variant.
There is additionally the initialization block, which is as well put in the constructor(s) by the compiler:
{
a = new A();
}
Check Sun's explanation and advice
From this tutorial:
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How do I create an array of strings in C?
...se pointers will then be set to the addresses of the static strings "blah" and "hmm".
If you do want to be able to change the actual string content, the you have to do something like
char a[2][14];
strcpy(a[0], "blah");
strcpy(a[1], "hmm");
This will allocate two consecutive arrays of 14 chars e...
What's the difference between @Component, @Repository & @Service annotations in Spring?
Can @Component , @Repository and @Service annotations be used interchangeably in Spring or do they provide any particular functionality besides acting as a notation device?
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Initialize class fields in constructor or at declaration?
I've been programming in C# and Java recently and I am curious where the best place is to initialize my class fields.
15 An...