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Can a constructor in Java be private?
...of delegating constructors, the following class allows you to save a value and a type, but it only lets you do it for a subset of types, so making the general constructor private is needed to ensure that only the permitted types are used. The common private constructor helps code reuse.
public clas...
PDO closing connection
...ber of other reasons. When connecting or running a query, catch any error, and if it is "MySQL has gone away", attempt to connect again or run the query a second time.
– Frank Forte
Dec 14 '17 at 20:50
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How to use the PI constant in C++
I want to use the PI constant and trigonometric functions in some C++ program. I get the trigonometric functions with include <math.h> . However, there doesn't seem to be a definition for PI in this header file.
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Stream vs Views vs Iterators
What are the differences among Streams, Views (SeqView), and Iterators in scala? This is my understanding:
1 Answer
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foldl versus foldr behavior with infinite lists
...r folding a list of n values [x1, x2, x3, x4 ... xn ] with some function f and seed z.
foldl is:
Left associative: f ( ... (f (f (f (f z x1) x2) x3) x4) ...) xn
Tail recursive: It iterates through the list, producing the value afterwards
Lazy: Nothing is evaluated until the result is needed
Backw...
Why do python lists have pop() but not push()
...ot called list.push given that there's already a list.pop that removes and returns the last element (that indexed at -1) and list.append semantic is consistent with that use?
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How can I delete all unversioned/ignored files/folders in my working copy?
...te all unversioned or ignored files in that working copy with a single command or tool? Essentially, I'm looking for the SVN analogue to git clean .
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When is a C++ destructor called?
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1) If the object is created via a pointer and that pointer is later deleted or given a new address to point to, does the object that it was pointing to call its destructor (assuming nothing else is pointing to it)?
It depends on the type of pointers. For example, s...
Git - working on wrong branch - how to copy changes to existing topic branch
...orking on a project, but unfortunately, I forgot to switch to my branch, and as such have been working on master
4 Answer...
What is difference between instantiating an object using new vs. without
...lock of memory by calling either ::operator new() or Time::operator new(), and subsequently calls Time::Time() with this set to an address within that memory block (and also returned as the result of new), which is then stored in t. As you know, this is generally done on the heap (by default) and re...