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How do I get the MIN() of two fields in Postgres?
...alue from a list of any number of expressions. The expressions must all be convertible to a common data type, which will be the type of the result (see Section 10.5 for details). NULL values in the list are ignored. The result will be NULL only if all the expressions evaluate to NULL.
Note that...
NSLog the method name with Objective-C in iPhone
... Method calls like [self doSomething:arg1 somethingElse:arg2] get converted into the C function call objc_msgSend(self, "doSomething:somethingElse:, arg1, arg2);. The second parameter of objc_msgSend() takes a char*. Remember that because the Objective-C runtime is dynamic, it's actually us...
Validating IPv4 addresses with regexp
...t also leads to difficulties with verification/security as 023 needs to be converted to 23 to avoid duplicates, etc. Thanks for trying to make things better !
– Danail Gabenski
Dec 27 '19 at 1:03
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Write to .txt file?
How can I write a little piece of text into a .txt file?
I've been Googling for over 3-4 hours, but can't find out how to do it.
...
How to check for an undefined or null variable in JavaScript?
... property doesn't yield an error and simply returns undefined, which, when converted to a boolean, evaluates to false. So, if you don't care about
0 and false, using if(obj.undefProp) is ok. There's a common idiom based on this fact:
value = obj.prop || defaultValue
which means "if obj has the p...
Zipping streams using JDK8 with lambda (java.util.stream.Streams.zip)
...iterator();
// Zipping looses DISTINCT and SORTED characteristics
int characteristics = aSpliterator.characteristics() & bSpliterator.characteristics() &
~(Spliterator.DISTINCT | Spliterator.SORTED);
long zipSize = ((characteristics & Spliterator.SIZED) != 0)
...
What is the Swift equivalent of respondsToSelector?
... func work() { }
func eat(food: AnyObject) { }
func sleep(hours: Int, minutes: Int) { }
}
let worker = Worker()
let canWork = worker.respondsToSelector(Selector("work")) // true
let canEat = worker.respondsToSelector(Selector("eat:")) // true
let canSleep = worker.respondsToSelector...
MySQL “incorrect string value” error when save unicode string in Django
...
results = cursor.fetchall()
for row in results:
sql = "ALTER TABLE `%s` convert to character set DEFAULT COLLATE DEFAULT" % (row[0])
cursor.execute(sql)
db.close()
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How do you produce a .d.ts “typings” definition file from an existing JavaScript library?
...ucco-and-Luke-Hoban-Inside-TypeScript at 00:33:52 they had built a tool to convert WebIDL and WinRT metadata into TypeScript d.ts
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How to write LaTeX in IPython Notebook?
...:
from IPython.display import display, Math, Latex
display(Math(r'F(k) = \int_{-\infty}^{\infty} f(x) e^{2\pi i k} dx'))
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