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What is the difference between ? and Object in Java generics?
... type of ?. Not everything matches Object, but everything matches ?.
int test1(List<?> l) {
return l.size();
}
int test2(List<Object> l) {
return l.size();
}
List<?> l1 = Lists.newArrayList();
List<Object> l2 = Lists.newArrayList();
test1(l1); // compiles because any...
Why does !{}[true] evaluate to true in JavaScript?
... Not if you do eval('{}[true]') or type it to console. Then e.g. als {}"test" is test or even {key:"value"}"test" is test.
– t.niese
Oct 31 '13 at 9:42
...
Floating point vs integer calculations on modern hardware
... * (double)tv.tv_usec);
# endif
}
template< typename Type >
void my_test(const char* name) {
Type v = 0;
// Do not use constants or repeating values
// to avoid loop unroll optimizations.
// All values >0 to avoid division by 0
// Perform ten ops/iteration to reduce
// impac...
WCF ServiceHost access rights
...seful when you need to host services inside visual studio for debugging or testing. Don't use this on production...
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SQL Server IN vs. EXISTS Performance
...
I've done some testing on SQL Server 2005 and 2008, and on both the EXISTS and the IN come back with the exact same actual execution plan, as other have stated. The Optimizer is optimal. :)
Something to be aware of though, EXISTS, IN, and ...
Literal notation for Dictionary in C#?
...like your code):
var data = new Dictionary<string, string>
{
{ "test", "val" },
{ "test2", "val2" }
};
In C# 6, you now have the option of using a more intuitive syntax with Dictionary as well as any other type that supports indexers. The above statement can be rewritten as:
var d...
How to create a new database using SQLAlchemy?
...per PostgreSQL command for it.
>>> conn.execute("create database test")
>>> conn.close()
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How to remove the first character of string in PHP?
...r[0] = null;
// replaced by �, but ok for echo
Exec time for 1.000.000 tests : 0.39602184295654 sec
Remove the first letter with substr()
$str = "hello";
$str = substr($str, 1);
Exec time for 1.000.000 tests : 5.153294801712 sec
Remove the first letter with ltrim()
$str = "hello";
$str...
Controlling maven final name of jar artifact
...
A bit of an update, 2.4 is the latest version. Still works fine though.
– PaulBGD
Aug 17 '14 at 20:21
1
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C# 4 default parameter values: How to assign a default DateTime/object value? [duplicate]
...r function, then you can initialize it to any value you want.
static void test(DateTime? dt = null)
{
if (dt == null)
{
dt = new DateTime(1981, 03, 01);
}
//...
}
You can call it with a named parameter like this:
test(dt: new DateTime(2010, 03, 01));
And with the defau...