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I want to get the type of a variable at runtime
...ific type, such as this:
val x: Any = 5
def f[T](v: T) = v match {
case _: Int => "Int"
case _: String => "String"
case _ => "Unknown"
}
f(x)
Here it doesn't matter what is the type of the variable, Any. What matters, what is checked is the type of 5, the value. In fact,...
Python loop that also accesses previous and next values
...
This should do the trick.
foo = somevalue
previous = next_ = None
l = len(objects)
for index, obj in enumerate(objects):
if obj == foo:
if index > 0:
previous = objects[index - 1]
if index < (l - 1):
next_ = objects[index + 1]
Her...
window.close and self.close do not close the window in Chrome
...ion" exploit. So code like this used to work in general:
open(location, '_self').close();
This is buggy behavior, IMO, and is now (as of roughly April 2015) mostly blocked. It will still work from injected code only if the tab is freshly opened and has no pages in the browsing history. So it'...
How can I have a newline in a string in sh?
...
What I did based on the other answers was
NEWLINE=$'\n'
my_var="__between eggs and bacon__"
echo "spam${NEWLINE}eggs${my_var}bacon${NEWLINE}knight"
# which outputs:
spam
eggs__between eggs and bacon__bacon
knight
...
How to read/process command line arguments?
...
from argparse import ArgumentParser
parser = ArgumentParser()
parser.add_argument("-f", "--file", dest="filename",
help="write report to FILE", metavar="FILE")
parser.add_argument("-q", "--quiet",
action="store_false", dest="verbose", default=True,
...
How do I know if a generator is empty from the start?
...quence in memory. So there's no backward traversal.
You could write a has_next function or maybe even slap it on to a generator as a method with a fancy decorator if you wanted to.
share
|
improve...
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...rrays causes the two arrays to be evaluated in boolean context (by
calling __bool__ in Python3 or __nonzero__ in Python2).
Your original code
mask = ((r["dt"] >= startdate) & (r["dt"] <= enddate))
selected = r[mask]
looks correct. However, if you do want and, then instead of a and b u...
Mapping over values in a python dictionary
...ch function; the easiest way to do this is to use a dict comprehension:
my_dictionary = {k: f(v) for k, v in my_dictionary.items()}
In python 2.7, use the .iteritems() method instead of .items() to save memory. The dict comprehension syntax wasn't introduced until python 2.7.
Note that there is ...
How to organize a node app that uses sequelize?
...e is cached after the first execution. nodejs.org/api/modules.html#modules_caching
– Casey Flynn
Mar 29 '13 at 7:17
2
...
What is the difference between ManualResetEvent and AutoResetEvent in .NET?
...ass ManualResetEventSample
{
private readonly ManualResetEvent _manualReset = new ManualResetEvent(false);
public void RunAll()
{
new Thread(Worker1).Start();
new Thread(Worker2).Start();
new Thread(Worker3).Start();
Consol...