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How do I check if a string contains another string in Swift?
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You can do exactly the same call with Swift:
Swift 4 & Swift 5
In Swift 4 String is a collection of Character values, it wasn't like this in Swift 2 and 3, so you can use this more concise code1:
let string = "hello Swift"
if string.contains("Swift") {
p...
MySQL check if a table exists without throwing an exception
What is the best way to check if a table exists in MySQL (preferably via PDO in PHP) without throwing an exception. I do not feel like parsing the results of "SHOW TABLES LIKE" et cetera. There must be some sort of boolean query?
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Convert nullable bool? to bool
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You ultimately have to decide what the null bool will represent. If null should be false, you can do this:
bool newBool = x.HasValue ? x.Value : false;
Or:
bool newBool = x.HasValue && x.Value;
Or:
bool newBool = x ?? false;
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Best way to compare two complex objects
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For value types, you can typically just call their Equals method. Even if the fields or properties were never explicitly assigned, they would still have a default value.
For reference types, you should first call ReferenceEquals, which checks for reference equality – this would serve as an ef...
What is the equivalent of “none” in django templates?
I want to see if a field/variable is none within a Django template. What is the correct syntax for that?
7 Answers
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How do I check if there are duplicates in a flat list?
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Use set() to remove duplicates if all values are hashable:
>>> your_list = ['one', 'two', 'one']
>>> len(your_list) != len(set(your_list))
True
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Setting onClickListener for the Drawable right of an EditText [duplicate]
...left, Drawable top,
Drawable right, Drawable bottom) {
if (left != null) {
drawableLeft = left;
}
if (right != null) {
drawableRight = right;
}
if (top != null) {
drawableTop = top;
}
if (bottom !...
What is the most accurate way to retrieve a user's correct IP address in PHP?
...VER variables headers available for IP address retrieval. I was wondering if there is a general consensus as to how to most accurately retrieve a user's real IP address (well knowing no method is perfect) using said variables?
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How do I programmatically determine if there are uncommitted changes?
In a Makefile, I'd like to perform certain actions if there are uncommitted changes (either in the working tree or the index). What's the cleanest and most efficient way to do that? A command that exits with a return value of zero in one case and non-zero in the other would suit my purposes.
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Ant task to run an Ant target only if a file exists?
Is there an ANT Task that would execute a block only if a given file exists? I have the problem that I have a generic ant script that should do some special processing but only if a specific configuration file is present.
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