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Does Java SE 8 have Pairs or Tuples?
...eems like it can be solved without using any kind of Pair structure. [Note from OP: here is the other correct answer.]
The short answer is no. You either have to roll your own or bring in one of the several libraries that implements it.
Having a Pair class in Java SE was proposed and rejected at...
Why is there no SortedList in Java?
...s SortedSet and NavigableSet interfaces and works as you'd probably expect from a list:
TreeSet<String> set = new TreeSet<String>();
set.add("lol");
set.add("cat");
// automatically sorts natural order when adding
for (String s : set) {
System.out.println(s);
}
// Prints out "cat" ...
Java Generics: Cannot cast List to List? [duplicate]
...t;? extends Tree> b1 = a1;
... because then you can only fetch things from b1, and they're guaranteed to be compatible with Tree. You can't call b1.add(...) precisely because the compiler won't know whether it's safe or not.
Have a look at this section of Angelika Langer's Java Generics FAQ fo...
No route matches “/users/sign_out” devise rails 3
... I did the test and it works for me. Don't forget that things change from one version to another (be it in Rails or Devise). Besides, logging out is state-changing behaviour which should not be done using GET methods (in my humble opinion).
– Jessie Dedecker
...
Using reCAPTCHA on localhost
...accurate, but there's an important caveat that stumped me: When migrating from reCAPTCHA v1 to v2, it is necessary to regenerate the API keys in order for this message to disappear. Further, and equally important, if you're like me and you setup test domains in your local/development environment b...
When should use Readonly and Get only properties
...Fuel = a; // Does not compile
f.FillFuelTank(10); // Value is changed from the method's code
}
Setting the private field of your class as readonly allows you to set the field value only once (using an inline assignment or in the class constructor).
You will not be able to change it later.
pu...
Get all related Django model objects
...bj._meta.get_fields() if issubclass(type(field), ForeignObjectRel)] (given from django.db.models.fields.related import ForeignObjectRel)
– driftcatcher
May 31 '18 at 20:41
add...
Handling specific errors in JavaScript (think exceptions)
...
To create custom exceptions, you can inherit from the Error object:
function SpecificError () {
}
SpecificError.prototype = new Error();
// ...
try {
throw new SpecificError;
} catch (e) {
if (e instanceof SpecificError) {
// specific error
} else {
thr...
What is the difference between ng-if and ng-show/ng-hide
...on assigned to ngIf evaluates to a false value then the element is removed from the DOM, otherwise a clone of the element is reinserted into the DOM.
<!-- when $scope.myValue is truthy (element is restored) -->
<div ng-if="1"></div>
<!-- when $scope.myValue is falsy (element i...
Checking if an object is a given type in Swift
...ld only use as without the ? if there is no way your program could recover from the object not being of that type because the program will immediately halt if it is not. Using the ? in the if statement allows the program to continue.
– drewag
Jun 6 '14 at 23:55...