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Should a return statement be inside or outside a lock?
...d then returning it (outside the lock), then I'd say that a simple "return foo" inside the lock is a lot simpler.
To show the difference in IL, lets code:
static class Program
{
static void Main() { }
static readonly object sync = new object();
static int GetValue() { return 5; }
...
Get keys from HashMap in Java
...HashMap contains more than one key. You can use keySet() to get the set of all keys.
team1.put("foo", 1);
team1.put("bar", 2);
will store 1 with key "foo" and 2 with key "bar". To iterate over all the keys:
for ( String key : team1.keySet() ) {
System.out.println( key );
}
will print "foo"...
dynamic_cast and static_cast in C++
...
Here's a rundown on static_cast<> and dynamic_cast<> specifically as they pertain to pointers. This is just a 101-level rundown, it does not cover all the intricacies.
static_cast< Type* >(ptr)
This takes the pointer in ptr and tries to safely cast it to a pointer of type Type...
Explain the encapsulated anonymous function syntax
...ression:
(function foo() {
alert(2 + 2);
}());
The Parentheses (formally called the Grouping Operator) can surround only expressions, and a function expression is evaluated.
The two grammar productions can be ambiguous, and they can look exactly the same, for example:
function foo () {} // ...
How do you add Boost libraries in CMakeLists.txt?
... it can also help to add this to your cmake file: ADD_DEFINITIONS( -DBOOST_ALL_NO_LIB ) otherwise you may run into stackoverflow.com/questions/28887680/…
– Stéphane
Jul 22 '15 at 16:08
...
What is the purpose of the single underscore “_” variable in Python?
...cate that part
of a function result is being deliberately ignored (Conceptually, it is being discarded.), as in code like:
label, has_label, _ = text.partition(':').
As part of a function definition (using either def or lambda), where
the signature is fixed (e.g. by a callback or parent class API), ...
How does Apple know you are using private API?
...since I do not work in the Apple review team.
1. otool -L
This will list all libraries the app has linked to. Something clearly you should not use, like IOKit and WebKit can be detected by this.
2. nm -u
This will list all linked symbols. This can detect
Undocumented C functions such as _UIIma...
How do I append one string to another in Python?
...ugh memory to resize the string, the original
string object at *pv is deallocated, *pv is set to NULL, an "out of
memory" exception is set, and -1 is returned. Else (on success) 0 is
returned, and the value in *pv may or may not be the same as on input.
As always, an extra byte is alloc...
Which comment style should I use in batch files?
...re expanded. Suppose you have (wrongly) set TARGET=C:\Program Files (x86)\"foo.exe", and inside a DO(..) expression you have :: echo %TARGET% you will get an error because the (x86) gets expanded before the whole expression gets evaluated, leading to an invalid DO(..) expression and very inexplicabl...
What is attr_accessor in Ruby?
...d. What it does is create more methods for you.
So this code here:
class Foo
attr_accessor :bar
end
is equivalent to this code:
class Foo
def bar
@bar
end
def bar=( new_value )
@bar = new_value
end
end
You can write this sort of method yourself in Ruby:
class Module
def v...