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Why must we define both == and != in C#?
...tors is present, it will use the default reference equality operator, that all objects have, there is not an overload for it.1
Knowing that this is the case, the real question is: Why was this designed in this way and why doesn't the compiler figure it out on its own? A lot people are saying this ...
No Exception while type casting with a null in java
...ty hence we need to typecast null in these cases:
class A {
public void foo(Long l) {
// do something with l
}
public void foo(String s) {
// do something with s
}
}
new A().foo((String)null);
new A().foo((Long)null);
Otherwise you couldn't call the method you need.
...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...ull
IL_0002: stloc.0 // s
IL_0003: ldloc.0 // s
IL_0004: callvirt System.String.get_Length
IL_0009: call System.Console.WriteLine
It is the callvirt opcode that throws the NullReferenceException and it does that when the first argument on the evaluation stack is a null ...
django: BooleanField, how to set the default value to true?
...
from django.db import models
class Foo(models.Model):
any_field = models.BooleanField(default=True)
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Can I call an overloaded constructor from another constructor of the same class in C#?
...r in C# is immediately after ":" after the constructor.
for example
class foo
{
public foo(){}
public foo(string s ) { }
public foo (string s1, string s2) : this(s1) {....}
}
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How should a model be structured in MVC? [closed]
...understand MVC-like patterns in the context of PHP-based web applications. All the external links that are used in the content are there to explain terms and concepts, and not to imply my own credibility on the subject.
The first thing that I must clear up is: the model is a layer.
Second: there ...
Difference between Mock / Stub / Spy in Spock test framework
... replacing a real one, returning something like null or 0 for each method call. You use a mock if you need a dummy instance of a complex class which would otherwise use external resources like network connections, files or databases or maybe use dozens of other objects. The advantage of mocks is tha...
How does password salt help against a rainbow table attack?
... attack. However, the methods I've seen to implement this don't seem to really make the problem harder.
10 Answers
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In Bash, how do I add a string after each line in a file?
...
Pure POSIX shell and sponge:
suffix=foobar
while read l ; do printf '%s\n' "$l" "${suffix}" ; done < file |
sponge file
xargs and printf:
suffix=foobar
xargs -L 1 printf "%s${suffix}\n" < file | sponge file
Using join:
suffix=foobar
join file file -e...
Understanding Python's “is” operator
What does it really mean?
11 Answers
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