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When should I use a struct rather than a class in C#?
...lass in C#? My conceptual model is that structs are used in times when the item is merely a collection of value types . A way to logically hold them all together into a cohesive whole.
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if a ngSrc path resolves to a 404, is there a way to fallback to a default?
...age is the center-piece of the application, so the broken image link makes it look like the whole thing is borked. I'd like to have another image take its place on a 404.
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Is it possible to remove inline styles with jQuery?
...g an inline style ( display:block ). I'm feeling lazy and want to override it with display:none .
15 Answers
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Why do this() and super() have to be the first statement in a constructor?
Java requires that if you call this() or super() in a constructor, it must be the first statement. Why?
19 Answers
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Android Fatal signal 11 (SIGSEGV) at 0x636f7d89 (code=1). How can it be tracked down?
...e=1 and code=2 . If the memory address was 0x00000000 , I'd have a clue it is a NullPointer.
23 Answers
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COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
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Bottom Line
Use either COUNT(field) or COUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely d...
Ruby, !! operator (a/k/a the double-bang) [duplicate]
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In most programming languages, including Ruby, ! will return the opposite of the boolean value of the operand. So when you chain two exclamation marks together, it converts the value to a boolean.
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How does the new automatic reference counting mechanism work?
Can someone briefly explain to me how ARC works? I know it's different from Garbage Collection, but I was just wondering exactly how it worked.
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Case objects vs Enumerations in Scala
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One big difference is that Enumerations come with support for instantiating them from some name String. For example:
object Currency extends Enumeration {
val GBP = Value("GBP")
val EUR = Value("EUR") //etc.
}
Then you can do:
val ccy = Currency.withName("EUR")
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Why should text files end with a newline?
I assume everyone here is familiar with the adage that all text files should end with a newline. I've known of this "rule" for years but I've always wondered — why?
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