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What is the formal difference in Scala between braces and parentheses, and when should they be used?
... boundaries of the expression.
Tuples
Because you can omit parenthesis sometimes, sometimes a tuple needs extra parenthesis like in ((1, 2)), and sometimes the outer parenthesis can be omitted, like in (1, 2). This may cause confusion.
Function/Partial Function literals with case
Scala has a syntax...
Haskell: Lists, Arrays, Vectors, Sequences
...
The first problem with lists is that to index into them (!!) takes ϴ(k) time, which is annoying. Also, appends can be slow ++, but Haskell's lazy evaluation model means that these can be treated as fully amortized, if they happen at all.
The second problem with lists is that they have poor data ...
How do I efficiently iterate over each entry in a Java Map?
If I have an object implementing the Map interface in Java and I wish to iterate over every pair contained within it, what is the most efficient way of going through the map?
...
What is the main difference between Inheritance and Polymorphism?
...entation of read, which method gets called is determined for you by the runtime, depending if you have a Person or a Student. It gets a bit tricky, but if you do something like
Person p = new Student();
p.read();
the read method on Student gets called. Thats the polymorphism in action. You can...
How do you install Google frameworks (Play, Accounts, etc.) on a Genymotion virtual device? [duplica
...ayer] [Error] [Adb][shell] Unable to finished process: "Process operation timed out"
Try to apply the flash using adbdirectly:
$ adb -s 192.168.56.101:5555 shell "/system/bin/check-archive.sh /sdcard/Download/gapps-jb-20121011-signed.zip"
$ adb -s 192.168.56.101:5555 shell "/system/bin/flash-ar...
PHP abstract properties
..., there is no way to enforce that with the compiler, you'd have to use run-time checks (say, in the constructor) for the $tablename variable, e.g.:
class Foo_Abstract {
public final function __construct(/*whatever*/) {
if(!isset($this->tablename))
throw new LogicException(get_class($...
What does “SyntaxError: Missing parentheses in call to 'print'” mean in Python?
...o!")?
Since the "Missing parentheses in call to print" case is a compile time syntax error and hence has access to the raw source code, it's able to include the full text on the rest of the line in the suggested replacement. However, it doesn't currently try to work out the appropriate quotes to p...
Replace specific characters within strings
...g regular expressions, which allow more flexible pattern matching but take time to compute. If all that's needed is removing a single constant string "e", they aren't necessary.
– mm689
Oct 31 '16 at 19:16
...
Why does Iterable not provide stream() and parallelStream() methods?
...t was just an omission. But you can see here that it was discussed several times over the years during the design of the API.
Lambda Libs Spec Experts
I found a discussion about this in the Lambda Libs Spec Experts mailing list:
Under Iterable/Iterator.stream() Sam Pullara said:
I was working...
Do sessions really violate RESTfulness?
...ate of this key must be maintained and it has some sort of expiration date/time after which it no longer grants access. However, as I mentioned at the top of my post, sacrifices must be made to allow an application to actually work. That said, authentication tokens must be stored in a way that all...