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Do I have to Close() a SQLConnection before it gets disposed?
Per my other question here about Disposable objects , should we call Close() before the end of a using block?
8 Answers
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Clojure: reduce vs. apply
... the ultimate result returned) for associative functions which need to see all their arguments in the variable-arity case. When they are result-wise equivalent, I'd say that apply is always perfectly idiomatic, while reduce is equivalent -- and might shave off a fraction of a blink of an eye -- in a...
Creating instance of type without default constructor in C# using reflection
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I originally posted this answer here, but here is a reprint since this isn't the exact same question but has the same answer:
FormatterServices.GetUninitializedObject() will create an instance without calling a constructor. I found...
What is the fastest way to check if a class has a function defined?
...tr() to get the attribute, and callable() to verify it is a method:
invert_op = getattr(self, "invert_op", None)
if callable(invert_op):
invert_op(self.path.parent_op)
Note that getattr() normally throws exception when the attribute doesn't exist. However, if you specify a default value (None...
How to check if an object is a list or tuple (but not string)?
...quence; otherwise, if it is indexable or iterable, it's a sequence:
def is_sequence(arg):
return (not hasattr(arg, "strip") and
hasattr(arg, "__getitem__") or
hasattr(arg, "__iter__"))
def srepr(arg):
if is_sequence(arg):
return '<' + ", ".join(srepr(x) f...
How to make a phone call in android and come back to my activity when the call is done?
...ener actions to wait for a the call to start (wait until changed from PHONE_STATE_OFFHOOK to PHONE_STATE_IDLE again) and then write some code to bring your app back up on the IDLE state.
you may need to run the listener in a service to ensure it stays up and your app is restarted. some example c...
Basic http file downloading and saving to disk in python?
...URLopener is deprecated.
And when used you will get error as below:
url_opener = urllib.URLopener() AttributeError: module 'urllib' has no
attribute 'URLopener'
So, try:
import urllib.request
urllib.request.urlretrieve(url, filename)
...
What is WEB-INF used for in a Java EE web application?
... within the application hierarchy named
WEB-INF. This directory contains all things related to the
application that aren’t in the document root of the application. The
WEB-INF node is not part of the public document tree of the
application. No file contained in the WEB-INF directory may be...
static const vs #define
...
Personally, I loathe the preprocessor, so I'd always go with const.
The main advantage to a #define is that it requires no memory to store in your program, as it is really just replacing some text with a literal value. It also has...
iOS 7 TableView like in Settings App on iPad
...lor = UIColor.clearColor;
CAShapeLayer *layer = [[CAShapeLayer alloc] init];
CGMutablePathRef pathRef = CGPathCreateMutable();
CGRect bounds = CGRectInset(cell.bounds, 10, 0);
BOOL addLine = NO;
if (indexPath.row == 0 && indexPath.r...