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Bytecode features not available in the Java language
...to exploit this "feature" in Java versions before 6:
class Foo {
public String s;
public Foo() {
System.out.println(s);
}
}
class Bar extends Foo {
public Bar() {
this(s = "Hello World!");
}
private Bar(String helper) {
super();
}
}
This way, a field could be set before...
Is there a performance difference between i++ and ++i in C++?
...n the following:
00401000 push 0Ah
00401002 push offset string "Value: %d\n" (402104h)
00401007 call dword ptr [__imp__printf (4020A0h)]
So while it's certainly the case that the postfix version could be slower, it may well be that the optimizer will be good enough to ...
Setting environment variables for accessing in PHP when using Apache
...
in xampp on windows the file will be C:\xampp\apache\conf\extra\httpd-vhosts.conf
– Dung
Apr 3 '17 at 19:09
...
What are some (concrete) use-cases for metaclasses?
...Model):
... foo = Integer()
...
>>> class B(A):
... bar = String()
...
>>> B._fields
{'foo': Integer('A.foo'), 'bar': String('B.bar')}
Again, this can be done (without inheritance) with a class decorator:
def model(cls):
fields = {}
for key, value in vars(cls).it...
PostgreSQL function for last inserted ID
...s some TRIGGER (or RULE) that, on insertion into persons table, makes some extra insertions in other tables... then LASTVAL will probably give us the wrong value. The problem can even happen with CURRVAL, if the extra insertions are done intto the same persons table (this is much less usual, but the...
How to Set Variables in a Laravel Blade Template
... (for instance) an operator such as ==.
@if ($variable = 'any data, be it string, variable or OOP') @endif
Then you can use it anywhere you can use any other variable
{{ $variable }}
The only downside is your assignment will look like a mistake to someone not aware that you're doing this as a ...
How do I get a Cron like scheduler in Python? [closed]
...None of the listed solutions even attempt to parse a complex cron schedule string. So, here is my version, using croniter. Basic gist:
schedule = "*/5 * * * *" # Run every five minutes
nextRunTime = getNextCronRunTime(schedule)
while True:
roundedDownTime = roundDownTime()
if (roundedDow...
Get size of all tables in database
...with filtered indexes: For each filtered index for a given table, I see an extra row with that tables's name in the results. The "RowCounts" of each of those extra rows corresponds to the number of rows covered by one of the filtered indexes. (on Sql2012)
– Akos Lukacs
...
Class does not implement its superclass's required members
... init, like so:
convenience required init(coder: NSCoder) {
self.init(stringParam: "", intParam: 5)
}
Note the call to an initializer in self. This allows you to only have to use dummy values for the parameters, as opposed to all non-optional properties, while avoiding throwing a fatal error....
Why doesn't await on Task.WhenAll throw an AggregateException?
...on and throws the underlying exception. By leveraging
await, you avoid the extra work to handle the AggregateException type
used by Task.Result, Task.Wait, and other Wait methods defined in the
Task class. That’s another reason to use await instead of the
underlying Task methods....
...