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What is the best way to implement nested dictionaries?
...ython?
This is a bad idea, don't do it. Instead, use a regular dictionary and use dict.setdefault where apropos, so when keys are missing under normal usage you get the expected KeyError. If you insist on getting this behavior, here's how to shoot yourself in the foot:
Implement __missing__ on a di...
Is unsigned integer subtraction defined behavior?
...ed type is well-defined:
[...] A computation involving unsigned operands can never overflow,
because a result that cannot be represented by the resulting unsigned integer type is
reduced modulo the number that is one greater than the largest value that can be
represented by the resultin...
What is the argument for printf that formats a long?
...
On most platforms, long and int are the same size (32 bits). Still, it does have its own format specifier:
long n;
unsigned long un;
printf("%ld", n); // signed
printf("%lu", un); // unsigned
For 64 bits, you'd want a long long:
long long n;
uns...
How to avoid isset() and empty()
I have several older applications that throw a lot of "xyz is undefined" and "undefined offset" messages when running on the E_NOTICE error level, because the existence of variables is not explicitly checked using isset() and consorts.
...
Simpler way to put PDB breakpoints in Python code?
...uestion. I've been a bit spoiled with debuggers in IDEs like Visual Studio and XCode. I find it a bit clumsy to have to type import pdb; pdb.set_trace() to set a breakpoint (I'd rather not import pdb at the top of the file as I might forget and leave it in).
...
How to get the entire document HTML as a string?
...
MS added the outerHTML and innerHTML properties some time ago.
According to MDN, outerHTML is supported in Firefox 11, Chrome 0.2, Internet Explorer 4.0, Opera 7, Safari 1.3, Android, Firefox Mobile 11, IE Mobile, Opera Mobile, and Safari Mobile. ...
When should I use a List vs a LinkedList
...his should not be an accepted answer. As I was
learning I did some tests and felt like sharing them.
Original answer...
I found interesting results:
// Temporary class to show the example
class Temp
{
public decimal A, B, C, D;
public Temp(decimal a, decimal b, decimal c, decimal d)
...
Using ping in c#
...s;
}
catch (PingException)
{
// Discard PingExceptions and return false;
}
finally
{
if (pinger != null)
{
pinger.Dispose();
}
}
return pingable;
}
...
How can I install pip on Windows?
...
Python 2.7.9+ and 3.4+
Good news! Python 3.4 (released March 2014) and Python 2.7.9 (released December 2014) ship with Pip. This is the best feature of any Python release. It makes the community's wealth of libraries accessible to everyon...
Global access to Rake DSL methods is deprecated
I am working through the Ruby on Rails 3 tutorial book and typed the following on the command line:
5 Answers
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