Questions tagged [reference]
A reference is a value that enables a program to indirectly access a particular datum, such as a variable or a record, in the computer's memory or in some other storage device.
reference
17,285
questions
3922
votes
44
answers
1.3m
views
What are the differences between a pointer variable and a reference variable?
What is the difference between a pointer variable and a reference variable?
- 59.5k
3315
votes
42
answers
2.1m
views
How do I pass a variable by reference?
I wrote this class for testing:
class PassByReference:
def __init__(self):
self.variable = 'Original'
self.change(self.variable)
print(self.variable)
def change(self, ...
- 49.4k
1490
votes
23
answers
1.2m
views
How to copy a dictionary and only edit the copy
I set dict2 = dict1. When I edit dict2, the original dict1 also changes. How can I avoid this?
>>> dict1 = {"key1": "value1", "key2": "value2"}
>>...
- 21k
1028
votes
28
answers
443k
views
What's the difference between the 'ref' and 'out' keywords?
I'm creating a function where I need to pass an object so that it can be modified by the function. What is the difference between:
public void myFunction(ref MyClass someClass)
and
public void ...
- 47.5k
921
votes
62
answers
1.4m
views
The located assembly's manifest definition does not match the assembly reference
I am trying to run some unit tests in a C# Windows Forms application (Visual Studio 2005), and I get the following error:
System.IO.FileLoadException: Could not load file or assembly 'Utility, ...
- 194k
917
votes
12
answers
258k
views
What's the difference between SoftReference and WeakReference in Java?
What's the difference between java.lang.ref.WeakReference and java.lang.ref.SoftReference ?
- 11.6k
638
votes
10
answers
246k
views
MongoDB relationships: embed or reference?
I want to design a question structure with some comments. Which relationship should I use for comments: embed or reference?
A question with some comments, like stackoverflow, would have a structure ...
- 197k
628
votes
13
answers
540k
views
Is there a difference between "==" and "is"?
My Google-fu has failed me.
In Python, are the following two tests for equality equivalent?
n = 5
# Test one.
if n == 5:
print 'Yay!'
# Test two.
if n is 5:
print 'Yay!'
Does this hold ...
- 45.5k
533
votes
16
answers
1.1m
views
The type or namespace name could not be found [duplicate]
I have a C# solution with several projects in Visual Studio 2010.
One is a test project (I'll call it "PrjTest"), the other is a Windows Forms Application project (I'll call it "PrjForm"). There is ...
- 15.4k
485
votes
13
answers
292k
views
Does JavaScript pass by reference? [duplicate]
Does JavaScript pass by references or pass by values?
Here is an example from JavaScript: The Good Parts. I am very confused about the my parameter for the rectangle function. It is actually undefined,...
- 4,997
466
votes
17
answers
253k
views
When should I use pointers instead of references in API-design?
I understand the syntax and general semantics of pointers versus references, but how should I decide when it is more-or-less appropriate to use references or pointers in an API?
Naturally some ...
- 7,391
459
votes
11
answers
279k
views
Why can't I make a vector of references?
When I do this:
std::vector<int> hello;
Everything works great. However, when I make it a vector of references instead:
std::vector<int &> hello;
I get horrible errors like
...
- 13.7k
435
votes
4
answers
65k
views
Why can't I store a value and a reference to that value in the same struct?
I have a value and I want to store that value and a reference to
something inside that value in my own type:
struct Thing {
count: u32,
}
struct Combined<'a>(Thing, &'a u32);
fn ...
- 420k
424
votes
4
answers
349k
views
JavaScript by reference vs. by value [duplicate]
I'm looking for some good comprehensive reading material on when JavaScript passes something by value and when by reference and when modifying a passed item affects the value outside a function and ...
- 701k
416
votes
1
answer
53k
views
Why does the Rust compiler not optimize code assuming that two mutable references cannot alias?
As far as I know, reference/pointer aliasing can hinder the compiler's ability to generate optimized code, since they must ensure the generated binary behaves correctly in the case where the two ...
- 4,324