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Java 8 Streams - collect vs reduce
...cat)
We would get the desired result, and it would even work in parallel.
However, we might not be happy about the performance! Such an
implementation would do a great deal of string copying, and the run
time would be O(n^2) in the number of characters. A more performant
approach wou...
Looking for simple Java in-memory cache [closed]
...kedHashMap isn't good enough), and which can be serialized to disk periodically.
9 Answers
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How to exit an if clause
...
Ideally you can achieve both, but there are times when you must trade good code for good performance. Those times are rare, especially when you are considering using Python. In other words: don't worry so much about function c...
Debugging with command-line parameters in Visual Studio
...
Spot on. But apparently in VS2017 it's not called "Debugging", but "Debug". We may never know why.
– OmarL
Oct 16 '17 at 14:43
3
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What is meant by 'first class object'?
...nction
literal) if it treats functions as
first-class objects. Specifically,
this means that the language supports
constructing new functions during the
execution of a program, storing them
in data structures, passing them as
arguments to other functions, and
returning them as the va...
get NSDate today, yesterday, this Week, last Week, this Month, last Month… variables
...ve the seconds into the day if you want
NSDate *today = [NSDate date];
// All intervals taken from Google
NSDate *yesterday = [today dateByAddingTimeInterval: -86400.0];
NSDate *thisWeek = [today dateByAddingTimeInterval: -604800.0];
NSDate *lastWeek = [today dateByAddingTimeInterval: -1209600.0]...
What is the 'pythonic' equivalent to the 'fold' function from functional programming?
...(xs):
return reduce(operator.mul, xs, 1)
Be aware that reduce is actually a foldl, in Haskell terms. There is no special syntax to perform folds, there's no builtin foldr, and actually using reduce with non-associative operators is considered bad style.
Using higher-order functions is quite p...
General suggestions for debugging in R
...orite debugging routine:
When an error occurs, the first thing that I usually do is look at the stack trace by calling traceback(): that shows you where the error occurred, which is especially useful if you have several nested functions.
Next I will set options(error=recover); this immediately sw...
Why do 64-bit DLLs go to System32 and 32-bit DLLs to SysWoW64 on 64-bit Windows?
...ve it.
SysWoW64 wasn't intended for the dlls of 64-bit systems, it's actually something like "Windows on Windows64", meaning the bits you need to run 32bit apps on a 64bit windows.
This article explains a bit:
"Windows x64 has a directory System32 that contains 64-bit DLLs (sic!). Thus native p...
Set a cookie to never expire
...
All cookies expire as per the cookie specification, so this is not a PHP limitation.
Use a far future date. For example, set a cookie that expires in ten years:
setcookie(
"CookieName",
"CookieValue",
time() + (10 * 3...