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Convert list to array in Java [duplicate]
...
Either:
Foo[] array = list.toArray(new Foo[0]);
or:
Foo[] array = new Foo[list.size()];
list.toArray(array); // fill the array
Note that this works only for arrays of reference types. For arrays of primitive types, use the tra...
Are PHP Variables passed by value or by reference?
... final test, var3: final test
Passed by value/reference example:
$var1 = "foo";
$var2 = "bar";
changeThem($var1, $var2);
print "var1: $var1, var2: $var2";
function changeThem($var1, &$var2){
$var1 = "FOO";
$var2 = "BAR";
}
output:
var1: foo, var2 BAR
Object variables passed by ref...
Get the name of an object's type
...quivalent of Java's class.getName()?
No.
ES2015 Update: the name of class Foo {} is Foo.name. The name of thing's class, regardless of thing's type, is thing.constructor.name. Builtin constructors in an ES2015 environment have the correct name property; for instance (2).constructor.name is "Number...
rsync error: failed to set times on “/foo/bar”: Operation not permitted
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If /foo/bar is on NFS (or possibly some FUSE filesystem), that might be the problem.
Either way, adding -O / --omit-dir-times to your command line will avoid it trying to set modification times on directories.
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Execute the setInterval function without delay the first time
...It's simplest to just call the function yourself directly the first time:
foo();
setInterval(foo, delay);
However there are good reasons to avoid setInterval - in particular in some circumstances a whole load of setInterval events can arrive immediately after each other without any delay. Anothe...
Strangest language feature
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These let you use the "WTF operator": (foo() != ERROR)??!??! cerr << "Error occurred" << endl;
– user168715
Jan 4 '10 at 21:39
57
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Default value of function parameter
....
For example, you can declare a function with no default arguments
void foo(int a, int b);
In order to call that function after such declaration you'll have to specify both arguments explicitly.
Later (further down) in the same translation unit, you can re-declare it again, but this time with...
TypeError: method() takes 1 positional argument but 2 were given
...
In Python, this:
my_object.method("foo")
...is syntactic sugar, which the interpreter translates behind the scenes into:
MyClass.method(my_object, "foo")
...which, as you can see, does indeed have two arguments - it's just that the first one is implicit, ...
How can I read a function's signature including default argument values?
...
import inspect
def foo(a, b, x='blah'):
pass
print(inspect.getargspec(foo))
# ArgSpec(args=['a', 'b', 'x'], varargs=None, keywords=None, defaults=('blah',))
However, note that inspect.getargspec() is deprecated since Python 3.0.
Python ...
C pointers : pointing to an array of fixed size
...such an array to a function is by using a pointer-to-array parameter
void foo(char (*p)[10]);
(in C++ language this is also done with references
void foo(char (&p)[10]);
).
This will enable language-level type checking, which will make sure that the array of exactly correct size is suppli...