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Most efficient way to determine if a Lua table is empty (contains no entries)?
... the context of lua 5.2 & 5.3, is that non locals are either upvals or _ENV lookups. An upval has to go through an extra layer of indirection, whereas an _ENV lookup is a table lookup. Whereas a local is a register in the VM
– Demur Rumed
Jul 28 '17 at 0:30...
Creating a UICollectionView programmatically
...wDataSource,UICollectionViewDelegateFlowLayout>
{
UICollectionView *_collectionView;
}
Implementation File:--
- (void)viewDidLoad
{
[super viewDidLoad];
self.view = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
UICollectionViewFlowLayout *layout=[[UICollect...
Select count(*) from multiple tables
...
Just because it's slightly different:
SELECT 'table_1' AS table_name, COUNT(*) FROM table_1
UNION
SELECT 'table_2' AS table_name, COUNT(*) FROM table_2
UNION
SELECT 'table_3' AS table_name, COUNT(*) FROM table_3
It gives the answers transposed (one row per table instead of ...
How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
...$dev/statistics";
my %stats = do {
opendir +(my $dh), $dir;
local @_ = readdir $dh;
closedir $dh;
map +($_, []), grep !/^\.\.?$/, @_;
};
if (-t STDOUT) {
while (1) {
print "\033[H\033[J", run();
my ($time, $us) = gettimeofday();
my ($sec, $min, $hour) = l...
Delete files older than 15 days using PowerShell
...n the $limit.
Get-ChildItem -Path $path -Recurse -Force | Where-Object { !$_.PSIsContainer -and $_.CreationTime -lt $limit } | Remove-Item -Force
# Delete any empty directories left behind after deleting the old files.
Get-ChildItem -Path $path -Recurse -Force | Where-Object { $_.PSIsContainer -and...
How can a LEFT OUTER JOIN return more records than exist in the left table?
...
Table1 Table2
_______ _________
1 2
2 2
3 5
4 6
SELECT Table1.Id, Table2.Id FROM Table1 LEFT OUTER JOIN Table2 ON Table1.Id=Table2.Id
Resu...
IIS Express Immediately shutting-down running site after stopping web application
...
64
Instead of hitting the (X) STOP button, you can use the Detach all menu item in the Debug menu....
How to use Single TextWatcher for multiple EditTexts?
...rSequence, int i, int i1, int i2) {
if(charSequence.hashCode() == first_edit_text.getText().hashCode()){
// do other things
}
if(charSequence.hashCode() == second_edit_text.getText().hashCode()){
// do other things
}
}
Or
If you want to use afterTextChanged comp...
Synchronous request in Node.js
...and pass to the next
endpoints =
[{ host: 'www.example.com', path: '/api_1.php' },
{ host: 'www.example.com', path: '/api_2.php' },
{ host: 'www.example.com', path: '/api_3.php' }];
async.mapSeries(endpoints, http.get, function(results){
// Array of results
});
...
Set markers for individual points on a line in Matplotlib
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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