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What is the purpose of the single underscore “_” variable in Python?
What is the meaning of _ after for in this code?
5 Answers
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What exceptions should be thrown for invalid or unexpected parameters in .NET?
What types of exceptions should be thrown for invalid or unexpected parameters in .NET? When would I choose one instead of another?
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When do I use fabs and when is it sufficient to use std::abs?
.... But when I use just cmath and std::abs , do I have to use std::fabs or fabs ? Or isn't this defined?
4 Answers
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Byte[] to InputStream or OutputStream
I have a blob column in my database table, for which I have to use byte[] in my Java program as a mapping and to use this data I have to convert it to InputStream or OutputStream . But I don't know what happens internally when I do so. Can anyone briefly explain me what's happening when I do th...
“x not in y” or “not x in y”
When testing for membership, we can use:
6 Answers
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ArrayList vs List in C#
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Yes, pretty much. List<T> is a generic class. It supports storing values of a specific type without casting to or from object (which would have incurred boxing/unboxing overhead when T is a value type in the ArrayList case). ArrayList simply stores object references. As a gener...
Can an array be top-level JSON-text?
...hey differ in which top-level elements they allow, but all allow an object or an array as the top-level element.
RFC 4627: Object or array. "A JSON text is a serialized object or array."
RFC 7159: Any JSON value. "A JSON text is a serialized value."
ECMA-404: Any JSON value. "A JSON text is ...
NSDefaultRunLoopMode vs NSRunLoopCommonModes
Whenever I try to download a big file behind UIScrollView , MPMapView or something, the downloading process gets halted as soon as I touch iPhone screen. Thankfully, an awesome blog post by Jörn suggests an alternative option, using NSRunLoopCommonModes for connection.
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Unique fields that allow nulls in Django
...ar field should be unique, but allow nulls in it, meaning I want to allow more than one record if bar field is null , but if it is not null the values must be unique.
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Proper practice for subclassing UIView?
I'm working on some custom UIView-based input controls, and I'm trying to ascertain proper practice for setting up the view. When working with a UIViewController, it's fairly simple to use the loadView and related viewWill , viewDid methods, but when subclassing a UIView, the closest methosds I...