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How to enumerate an enum
...tAllSelectedItems<T>(this Enum value)
{
int valueAsInt = Convert.ToInt32(value, CultureInfo.InvariantCulture);
foreach (object item in Enum.GetValues(typeof(T)))
{
int itemAsInt = Convert.ToInt32(item, CultureInfo.InvariantCulture);
if (ite...
Why does comparing strings using either '==' or 'is' sometimes produce a different result?
...
One last thing to note, you may use the sys.intern function to ensure that you're getting a reference to the same string:
>>> from sys import intern
>>> a = intern('a')
>>> a2 = intern('a')
>>> a is a2
True
As pointed out abov...
What is an unsigned char?
...nsigned.
Now, i had a discussion with someone about what happens when you convert the value -1 of type int to unsigned char. He refused the idea that the resulting unsigned char has all its bits set to 1, because he was worried about sign representation. But he don't have to. It's immediately follo...
Value of type 'T' cannot be converted to
...xception, just like with any invalid cast. But I don't see why it couldn't convert to object and then to T. I agree with Triynko, although I suppose the designers had boxing/unboxing in mind.
– Fernando Gómez
May 30 '19 at 23:32
...
How do I get currency exchange rates via an API such as Google Finance? [closed]
...
Thanks for all your answers.
Free currencyconverterapi:
Rates updated every 30 min
API key is now required for the free server.
A sample conversion URL is: http://free.currencyconverterapi.com/api/v5/convert?q=EUR_USD&compact=y
For posterity here they are alon...
Java rounding up to an int using Math.ceil
... using either option 1 or option 2. Please do NOT use option 0.
##Option 0
Convert a and b to a double, and you can use the division and Math.ceil as you wanted it to work. However I strongly discourage the use of this approach, because double division can be imprecise. To read more about imprecisio...
Showing the stack trace from a running Python application
...'s dump). Here is an implementation based on this blog:
import threading, sys, traceback
def dumpstacks(signal, frame):
id2name = dict([(th.ident, th.name) for th in threading.enumerate()])
code = []
for threadId, stack in sys._current_frames().items():
code.append("\n# Thread:...
Using print statements only to debug
...le log methods, debug, info, warning, error and critical.
import logging, sys
logging.basicConfig(stream=sys.stderr, level=logging.DEBUG)
logging.debug('A debug message!')
logging.info('We processed %d records', len(processed_records))
...
Why does Python use 'magic methods'?
...those operations that
were generic for a group of types and
which were intended to work even for
objects that didn’t have methods at
all (e.g. tuples). It is also
convenient to have a function that can
readily be applied to an amorphous
collection of objects when you use the
functi...
How do I make the return type of a method generic?
...tic T ConfigSetting<T>(string settingName)
{
return /* code to convert the setting to T... */
}
But the caller will have to specify the type they expect. You could then potentially use Convert.ChangeType, assuming that all the relevant types are supported:
public static T ConfigSettin...