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How to check if a symlink exists
I'm trying to check if a symlink exists in bash. Here's what I've tried.
8 Answers
8
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String comparison in Python: is vs. == [duplicate]
...built-in Python objects (like
strings, lists, dicts, functions,
etc.), if x is y, then x==y is also
True.
Not always. NaN is a counterexample. But usually, identity (is) implies equality (==). The converse is not true: Two distinct objects can have the same value.
Also, is it generall...
How can I change the image displayed in a UIImageView programmatically?
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If you have an IBOutlet to a UIImageView already, then all you have to do is grab an image and call setImage on the receiver (UIImageView). Two examples of grabbing an image are below. One from the Web, and one you add to you...
Check if a string contains a number
... like to be a numberless string.
I need to enter a string and check to see if it contains any numbers and if it does reject it.
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jquery select change event get selected option
...ture stated there is obviously jQuery( selector [, context ] ). @Bellash: if it's "almost the same", what is the difference? Or what is faster? I prefer .find() since this is more OO IMO...
– Adrian Föder
May 7 '14 at 6:54
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How to set layout_weight attribute dynamically from code?
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If you don't want to cast from a double to a float just put 1.0f
– Xample
Jun 21 '12 at 14:58
9
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How do I concatenate two text files in PowerShell?
...nedFile.txt
You can concatenate more than two files with this style, too.
If the source files are named similarly, you can use wildcards:
Get-Content inputFile*.txt | Set-Content joinedFile.txt
Note 1: PowerShell 5 and older versions allowed this to be done more concisely using the aliases cat and...
SQL update query using joins
... 34
To make it clear... The UPDATE clause can refer to an table alias specified in the FROM clause. So im in this case is valid
Generic example
UPDATE A
SET foo = B.bar
FROM TableA A
JOIN TableB B
ON A.col1 = B.colx
WHERE ...
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UIButton: set image for selected-highlighted state
... @stephen: Setting the "Background"(image) property of UIButton for different conditions of "StateConfig"(Default/Highlighted/Selected/Disabled) Property works for me.
– Ajeet
Dec 10 '12 at 16:58
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Android: how do I check if activity is running?
...per.onStop();
active = false;
}
}
The only gotcha is that if you use it in two activities that link to each other then onStop on the first is sometimes called after onStart in second. So both might be true briefly.
Depending on what you are trying to do (update the current activity...