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Is it a good practice to use try-except-else in Python?
...ntrol."
In the Python world, using exceptions for flow control is common and normal.
Even the Python core developers use exceptions for flow-control and that style is heavily baked into the language (i.e. the iterator protocol uses StopIteration to signal loop termination).
In addition, the try...
How do I read / convert an InputStream into a String in Java?
...ou have a java.io.InputStream object, how should you process that object and produce a String ?
59 Answers
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Why does sizeof(x++) not increment x?
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From the C99 Standard (the emphasis is mine)
6.5.3.4/2
The sizeof operator yields the size (in bytes) of its operand, which may be an expression or the parenthesized name of a type. The size is determined from the type of the opera...
Open file dialog and select a file using WPF controls and C#
I have a TextBox named textbox1 and a Button named button1 .
When I click on button1 I want to browse my files to search only for image files (type jpg, png, bmp...).
And when I select an image file and click Ok in the file dialog I want the file directory to be written in the textbox1.tex...
How to exit if a command failed?
I am a noob in shell-scripting. I want to print a message and exit my script if a command fails. I've tried:
8 Answers
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How to create dictionary and add key–value pairs dynamically?
...Basically, you're creating an object literal with 2 properties (called key and value) and inserting it (using push()) into the array.
Edit: So almost 5 years later, this answer is getting downvotes because it's not creating an "normal" JS object literal (aka map, aka hash, aka dictionary).
It is ...
Unable to find specific subclass of NSManagedObject
...r Xcode 7 (final):
Prepending the module name to the class (as in Xcode 6 and early beta releases of Xcode 7) is no longer necessary.
The Apple documentation Implementing Core Data Managed Object Subclasses has been
updated accordingly.
The Data Model inspector
has now two fields "Class" and "Mod...
How do I create a constant in Python?
...ng on other people's work, I have added an answer, far below, with a short and simple implementation of "Constants" for python 2.7 (which lacks "enum"). These are enum-like read-only name.attribute, and can contain any value. Declaration is easy Nums = Constants(ONE=1, PI=3.14159, DefaultWidth=100.0...
performSelector may cause a leak because its selector is unknown
...s for a reason. It's very rare that this warning should simply be ignored, and it's easy to work around. Here's how:
if (!_controller) { return; }
SEL selector = NSSelectorFromString(@"someMethod");
IMP imp = [_controller methodForSelector:selector];
void (*func)(id, SEL) = (void *)imp;
func(_contr...
Chaining multiple filter() in Django, is this a bug?
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The way I understand it is that they are subtly different by design (and I am certainly open for correction): filter(A, B) will first filter according to A and then subfilter according to B, while filter(A).filter(B) will return a row that ma...