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Python: Find in list
...ll you need to know is whether something is a member of your list, you can convert the list to a set first and take advantage of constant time set lookup:
my_set = set(my_list)
if item in my_set: # much faster on average than using a list
# do something
Not going to be the correct solution i...
Differences between C++ string == and compare()?
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std::string::compare() returns an int:
equal to zero if s and t are equal,
less than zero if s is less than t,
greater than zero if s is greater than t.
If you want your first code snippet to be equivalent to the second one, it should actually read:
if (...
Routing for custom ASP.NET MVC 404 Error page
...hat do match one of the earlier rout patterns. Bad on principle because it converts what should be an error to not an error. Redirecting to a page you've named "Error" is different than redirecting to an error page. You want to keep it as an error, log the error, then handle it as an error. Errors a...
How to pass parameters correctly?
...gue that for fundamental types or types for which copying is fast, such as int, bool, or char, there is no need to pass by reference if the function simply needs to observe the value, and passing by value should be favored. That is correct if reference semantics is not needed, but what if the functi...
PopupWindow - Dismiss when clicked outside
...ndow on my activity, the thing is my PopupWindow still shows even when I'm interacting with my activity (say scrolling on my list). I can scroll through my list and the PopupWindow is still there.
...
How can I remove an entry in global configuration with git config?
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"You can tell Git to convert CRLF to LF on commit but not the other way around by setting core.autocrlf to input:" From: git-scm.com/book/en/v2/…
– colin_froggatt
May 6 '15 at 13:11
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Replacement for “rename” in dplyr
...umn names. This example replaces spaces and periods with an underscore and converts everything to lower case:
iris %>%
select_all(~gsub("\\s+|\\.", "_", .)) %>%
select_all(tolower) %>%
head(2)
sepal_length sepal_width petal_length petal_width species
1 5.1 3.5 ...
How do I programmatically “restart” an Android app?
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You can use PendingIntent to setup launching your start activity in the future and then close your application
Intent mStartActivity = new Intent(context, StartActivity.class);
int mPendingIntentId = 123456;
PendingIntent mPendingIntent = Pend...
What is a singleton in C#?
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sure, i am NOT pointing you are wrong. i am giving a hint to the reader about thread-safety, so that they would be careful if they have to deal with it.
– Alagesan Palani
Apr 6 '15 at 17:18
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Why is it OK to return a 'vector' from a function?
...ause the array return will (if you write it in the simple form) return a pointer to the actual array on the stack, which is then promptly removed when the function returns.
But in this case, it works, because the std::vector is a class, and classes, like structs, can (and will) be copied to the ca...