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What does immutable mean?
If a string is immutable, does that mean that....
(let's assume JavaScript)
9 Answers
...
Can we make unsigned byte in Java
...e in unsigned. The problem is the data I am receiving is unsigned and Java does not support unsigned byte, so when it reads the data it treats it as signed.
...
What happens to C# Dictionary lookup if the key does not exist?
...
Assuming you want to get the value if the key does exist, use Dictionary<TKey, TValue>.TryGetValue:
int value;
if (dictionary.TryGetValue(key, out value))
{
// Key was in dictionary; "value" contains corresponding value
}
else
{
// Key wasn't in dictiona...
What's the purpose of the LEA instruction?
...onathanDickinson LEA is like a MOV with an indirect source, except it only does the indirection and not the MOV. It doesn't actually read from the computed address, just computes it.
– hobbs
Aug 28 '13 at 2:57
...
How does Google calculate my location on a desktop?
...tion API) your computer sends the wifi identifiers it sees, and the system does two things:
queries its database if geolocation exists for some of the wifis you passed, and returns the "wardrived" position if found, eventually with triangulation if intensities are present. The more wifi networks a...
What does “use strict” do in JavaScript, and what is the reasoning behind it?
... octal syntax (var x = 023; some devs assume wrongly that a preceding zero does nothing to change the number.)
Forbids the with keyword
eval in strict mode does not introduce new variables
Forbids deleting plain names (delete x;)
Forbids binding or assignment of the names eval and arguments in a...
Xcode doesn't see my iOS device but iTunes does
...f it is not ready for development then click use for development.
If above doesn't solve your problem then from your project settings, set deployment target to one which your app is developed for or lesser.
Otherwise there is some issue with certificates and provisioning profiles. Make sure your dev...
How to mkdir only if a directory does not already exist?
...ot want to do anything. So I want to either test to see that the directory does not exist, or suppress the "File exists" error that mkdir throws when it tries to create an existing directory.
...
How does the HyperLogLog algorithm work?
...htforward way of doing it (having a set and adding elements to the set) it does this in an approximate way.
Before looking how the HyperLogLog algorithm does this, one has to understand why you need it. The problem with a straightforward way is that it consumes O(distinct elements) of space. Why th...
Rails and PostgreSQL: Role postgres does not exist
...
This message pops up, when the database user does not exist. Compare the manual here.
Multiple local databases cannot be the explanation. Roles are valid cluster-wide. The manual again:
Note that roles are defined at the database cluster level, and so are
valid in...