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Deep copying an NSArray
Is there any built-in function that allows me to deep copy an NSMutableArray ?
6 Answers
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How to get a list of file names in different lines
I want to get a list of all the files in a directory, like with ls , so that each filename will be on a seperate line, without the extra details supplied by ls -l . I looked at ls --help and didn't find a solution. I tried doing
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ffmpeg - Converting MOV files to MP4 [closed]
I have just installed ffmpeg and I am trying to encode all my uploaded videos to .mp4 file. Most of the users currently upload .mov and I want to convert every video to .mp4.
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What does Serializable mean?
...it is an interface that if implemented in a class, this class can automatically be serialized and deserialized by different serializers.
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JPA OneToMany not deleting child
...em with a simple @OneToMany mapping between a parent and a child entity. All works well, only that child records are not deleted when I remove them from the collection.
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how can you easily check if access is denied for a file in .NET?
Basically, I would like to check if I have rights to open the file before I actually try to open it; I do not want to use a try/catch for this check unless I have to. Is there a file access property I can check before hand?
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Elegant way to check for missing packages and install them?
...em are novice/intermediate R users and don't realize that they have to install packages they don't already have.
29 Answers...
Check Whether a User Exists
...t, you got command return value ($?)1
And as other answers pointed out: if all you want is just to check if the user exists, use if with id directly, as if already checks for the exit code. There's no need to fiddle with strings, [, $? or $():
if id "$1" &>/dev/null; then
echo 'user found...
How do I check if an element is hidden in jQuery?
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I actually found that the reverse logic words better: !$('selector').is(':hidden'); for some reason. Worth a try.
– Kzqai
Jan 5 '12 at 15:36
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How do I disable form fields using CSS?
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That looked like just what I was after to disable all my input fields but, although it blocks them from mouse events, they can still be accessed and changed using keyboard tab
– Ken
Oct 20 '15 at 15:18
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