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Performance difference between IIf() and If
...er is about the side-effects. The performance isn’t really relevant when one of the options is obsolete. For what it’s worth, the native operator If is more efficient than the IIf function by far.
– Konrad Rudolph
May 4 '15 at 12:32
...
How to validate an email address in JavaScript
....,;:\s@\"]+\.)+[^<>()[\]\.,;:\s@\"]{2,})$/i;
But keep in mind that one should not rely only upon JavaScript validation. JavaScript can easily be disabled. This should be validated on the server side as well.
Here's an example of the above in action:
function validateEmail(email) {
c...
How to get the path of a running JAR file?
...roblems with special characters, including spaces and pluses. The correct one-liner is: return new File(MyClass.class.getProtectionDomain().getCodeSource().getLocation().toURI()); Using URLDecoder does not work for many special characters. See my answer below for further details.
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SQL Data Reader - handling Null column values
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If someone needs the column name rather than the index, you can do: int colIndex = reader.GetOrdinal(fieldname); and easily overload @marc_s's SafeGetString function.
– ilans
Feb 15 '15 at 13:0...
How to increment datetime by custom months in python without using library [duplicate]
...ce the month in original date to January whereas passing months=1 will add one month to original date.
Note: this will requires python-dateutil. To install it you need to run in Linux terminal.
sudo apt-get update && sudo apt-get install python-dateutil
Explanation : Add month value in p...
top -c command in linux to filter processes listed based on processname
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It can be done interactively
After running top -c , hit o and write a filter on a column, e.g. to show rows where COMMAND column contains the string foo, write COMMAND=foo
If you just want some basic output this might be enough:
top ...
Learning to write a compiler [closed]
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I think one worth mentioning is Coursera's compilers course. It has nice videos and walks through creating a java like language / simple compiler. Coursera Compilers Link
– QuantumKarl
Feb 24 '1...
What's the best way to parse command line arguments? [closed]
...u are better off going with optparse over getopt. getopt is pretty much a one-to-one mapping of the standard getopt(3) C library functions, and not very easy to use.
optparse, while being a bit more verbose, is much better structured and simpler to extend later on.
Here's a typical line to add an...
C/C++ Struct vs Class
...fault to public in structs—a struct written like a C struct behaves like one.)
While it's possible to fake some OOP in C—for instance, defining functions which all take a pointer to a struct as their first parameter, or occasionally coercing structs with the same first few fields to be "sub/sup...
round() for float in C++
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There's no round() in the C++98 standard library. You can write one yourself though. The following is an implementation of round-half-up:
double round(double d)
{
return floor(d + 0.5);
}
The probable reason there is no round function in the C++98 standard library is that it can in f...