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Should the hash code of null always be zero, in .NET
...the same hash code.
Returning 0 or -1 for null, so long as you choose one and return it all the time, will work. Obviously, non-null hash codes should not return whatever value you use for null.
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GetHashCode on null fields?
What should GetHashCode return when object's identifie...
How do I disable text selection with CSS or JavaScript? [duplicate]
... edited Jun 1 '15 at 17:08
Andy
1,4461515 silver badges3333 bronze badges
answered Sep 23 '10 at 14:44
Je...
How to Correctly Use Lists in R?
...st?) contemporary programming languages in widespread use have at least a handful of ADTs [abstract data types] in common, in particular,
...
Check if database exists in PostgreSQL using shell
...rows" will succeed. So we pipe this output through a bunch of built-in command line tools to only search in the first column.
The -t flag removes headers and footers:
my_db | my_user | UTF8 | en_US.UTF8 | en_US.UTF8 |
postgres | postgres | LATIN1 | en_US | en_US |
te...
John Carmack's Unusual Fast Inverse Square Root (Quake III)
...code below. Can someone explain line by line what exactly is going on here and why this works so much faster than the regular implementation?
...
Testing whether a value is odd or even
I decided to create simple isEven and isOdd function with a very simple algorithm:
22 Answers
...
Django filter versus get for single object?
...lly implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're violating one of the cardinal rules of programming, namely trying to optimize code before it's even been written and profiled -- until you have the code and can run ...
Extract hostname name from string
I would like to match just the root of a URL and not the whole URL from a text string. Given:
27 Answers
...
Trying to embed newline in a variable in bash [duplicate]
...n the source code
p="${var1}
${var2}"
echo "${p}"
Using $'\n' (only bash and zsh)
p="${var1}"$'\n'"${var2}"
echo "${p}"
Details
1. Inserting \n
p="${var1}\n${var2}"
echo -e "${p}"
echo -e interprets the two characters "\n" as a new line.
var="a b c"
first_loop=true
for i in $var
do
p="...
What does $$ mean in the shell?
...me for a variety of reasons.
For temporary file names, use the mktemp command.
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