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JavaScript isset() equivalent
...
Age old thread, but there are new ways to run an equivalent isset().
ESNext (Stage 4 December 2019)
Two new syntax allow us to vastly simplify the use of isset() functionality:
Optional Chaining(?.)
Nullish Coalescing Operator(??)
Pl...
Assignment in an if statement
...s though. It's not terribly unusual for me to do it in a while though when reading streams of data. For example:
string line;
while ((line = reader.ReadLine()) != null)
{
...
}
These days I normally prefer to use a wrapper which lets me use foreach (string line in ...) but I view the above as...
What is the difference between a string and a byte string?
...In Python, a byte string is just that: a sequence of bytes. It isn't human-readable. Under the hood, everything must be converted to a byte string before it can be stored in a computer.
On the other hand, a character string, often just called a "string", is a sequence of characters. It is human-rea...
Why do python lists have pop() but not push()
...on's list.append function is not 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?
...
Is there a way to change the environment variables of another process in Unix?
...t be changed from the outside after startup, hence most will probably just read the vars they are interested in at startup and initialize based on that. So changing them afterwards will not make a difference, since the program will never re-read them.
If you posted this as a concrete problem, you s...
Find an element in a list of tuples
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Read up on List Comprehensions
[ (x,y) for x, y in a if x == 1 ]
Also read up up generator functions and the yield statement.
def filter_value( someList, value ):
for x, y in someList:
if x == value :
...
Domain Driven Design: Domain Service, Application Service
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(If you don't feel like reading, there's a summary at the bottom :-)
I too have struggled with the precise definition of application services. Although Vijay's answer was very helpful to my thinking process a month ago, I have come to disagree with...
Haskell error parse error on input `='
... @Bakuriu LYAH does now mention let. But a follow-up. In LYAH I read addThree :: Int -> Int -> Int -> Int (newline) addThree x y z = x + y + z but only the second one runs in GHCi with let. Why?
– isomorphismes
Aug 5 '13 at 15:33
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How to solve Permission denied (publickey) error when using Git?
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This error can happen when you are accessing the SSH URL (Read/Write) instead of Git Read-Only URL but you have no write access to that repo.
Sometimes you just want to clone your own repo, e.g. deploy to a server. In this case you actually only need READ-ONLY access. But since tha...
Can we instantiate an abstract class?
...mous subclass.
Emphasis mine.
Also, in JLS - Section # 12.5, you can read about the Object Creation Process. I'll quote one statement from that here: -
Whenever a new class instance is created, memory space is allocated
for it with room for all the instance variables declared in the clas...