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How do I check if a list is empty?
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Playing devil's advocate. I don't understand why this idiom is considered pythonic. 'Explicit is better then implicit', correct? This check doesn't seem very explicit about what is is checking.
– James McMahon
Nov 22 '11 at 6:1...
Is it safe to delete a NULL pointer?
...elete performs the check anyway, so checking it on your side adds overhead and looks uglier. A very good practice is setting the pointer to NULL after delete (helps avoiding double deletion and other similar memory corruption problems).
I'd also love if delete by default was setting the parameter t...
How do I do a multi-line string in node.js?
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node v4 and current versions of node
As of ES6 (and so versions of Node greater than v4), a new "template literal" intrinsic type was added to Javascript (denoted by back-ticks "`") which can also be used to construct multi-line str...
Should I avoid the use of set(Preferred|Maximum|Minimum)Size methods in Java Swing?
...ity between systems with different screen resolution.)
Some (incomplete, and unfortunately the links are broken due to migration of SwingLabs to java.net) technical reasons are for instance mentioned in the Rules (hehe) or in the link @bendicott found in his/her comment to my answer. Socially, pos...
How can I let a table's body scroll but keep its head fixed in place?
...zontal scroll). You'll have two horizontal scrollbars; one for the header and one for the data.
– vol7ron
Aug 18 '11 at 21:41
4
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What does “static” mean in C?
...l for cases where a function needs to keep some state between invocations, and you don't want to use global variables. Beware, however, this feature should be used very sparingly - it makes your code not thread-safe and harder to understand.
(2) Is used widely as an "access control" feature. If you...
Float vs Decimal in ActiveRecord
...ation defines floats in binary format. Basically, it stores sign, fraction and exponent to represent a Float. It's like a scientific notation for binary (something like +1.43*10^2). Because of that, it is impossible to store fractions and decimals in Float exactly.
That's why there is a Decimal for...
The difference between try/catch/throw and try/catch(e)/throw e
...milar in that both will catch every exception thrown inside the try block (and, unless you are simply using this to log the exceptions, should be avoided). Now look at these:
try { ... }
catch ()
{
/* ... */
throw;
}
try { ... }
catch (Exception e)
{
/* ... */
throw;
}
try { ... }...
Immutable vs Mutable types
... changing what the variable refers to. A mutable type can change that way, and it can also change "in place".
Here is the difference.
x = something # immutable type
print x
func(x)
print x # prints the same thing
x = something # mutable type
print x
func(x)
print x # might print something differe...
“inconsistent use of tabs and spaces in indentation”
I'm trying to create an application in Python 3.2 and I use tabs all the time for indentation, but even the editor changes some of them into spaces and then print out "inconsistent use of tabs and spaces in indentation" when I try to run the program.
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