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Is there a performance difference between a for loop and a for-each loop?
... iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
doSomething(e);
}
When you see the colon (:), read it as
“in.” Thus, the loop ab...
Access nested dictionary items via a list of keys?
...ist, value):
getFromDict(dataDict, mapList[:-1])[mapList[-1]] = value
All but the last element in mapList is needed to find the 'parent' dictionary to add the value to, then use the last element to set the value to the right key.
Demo:
>>> getFromDict(dataDict, ["a", "r"])
1
>>&g...
What does 'COLLATE SQL_Latin1_General_CP1_CI_AS' do?
...parts:
latin1 makes the server treat strings using charset latin 1, basically ascii
CP1 stands for Code Page 1252
CI case insensitive comparisons so 'ABC' would equal 'abc'
AS accent sensitive, so 'ü' does not equal 'u'
P.S. For more detailed information be sure to read @solomon-rutzky's answer...
Difference between abstract class and interface in Python
... @L.DeLeo - are you sure your notion of has-a vs. is-a is correct? I generally view the distinction as has-a = member variable vs. is-a = inheritance (parent class or interface). Think Comparable or List in Java; those are is-a relationships, regardless of whether they're interfaces or abstract cl...
vbscript output to console
...aples - Not w/ the stock WScript.Echo. I suppose, if you wanted to stay totally within WScript you could do something horrifyingly dodgy like Exec'ing off another process to do a "SendKeys" to the parent process to close the MessageBox.
– Evan Anderson
Jun 22 '...
What is the purpose of class methods?
...sson was that Python is not Java , and so I've just spent a while turning all my Class methods into functions.
17 Answers
...
How many concurrent AJAX (XmlHttpRequest) requests are allowed in popular browsers?
... No, the limits are imposed on the domain. So you could technically get FF up to 12 connections if you had a subdomain in addition to your site.
– Bob
Feb 18 '09 at 13:39
...
Extract traceback info from an exception object
...ion("foo occurred").with_traceback(tracebackobj)
These features are minimally described as part of the raise documentation.
All credit for this part of the answer should go to Vyctor, who first posted this information. I'm including it here only because this answer is stuck at the top, and Python...
Can I create links with 'target=“_blank”' in Markdown?
...rget="_blank">Hello, world!</a>
Most Markdown engines I've seen allow plain old HTML, just for situations like this where a generic text markup system just won't cut it. (The StackOverflow engine, for example.) They then run the entire output through an HTML whitelist filter, regardless, ...
detach all packages while working in R
...*) is not necessary but can be useful to prevent the NULL reply from vertically spamming the R window.
(edit: 9/20/2019) In version 3.6.1
It may be helpful to convert loaded only names(sessionInfo()$loadedOnly) to explicitly attached packages first, and then detach the packages, as so.
lapply(names(...