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Hidden features of Perl?
...
One of my favourite features in Perl is using the boolean || operator to select between a set of choices.
$x = $a || $b;
# $x = $a, if $a is true.
# $x = $b, otherwise
This means one can write:
$x = $a || $b || $c || 0;
to take the first true value from $a, $b, and $c, or a default of 0...
How to run a method every X seconds
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Spot on! Using for checking MainActivitys current selected tab in TabLayout matches this fragment and if not stop work - as onPause() fails when any TabLayout selected tabs either side of this selected tab
– BENN1TH
Oct 20 '18 at 7:29
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How do I get the APK of an installed app without root access?
...e your device try (re)installing USB-Driver for your
device
In middle pane select tab "File Explorer" and go to system > app
Now you can select one or more files and then click the "Pull a file
from the device" icon at the top (right to the tabs)
Select target folder - tada!
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How to display the current year in a Django template?
...ration year dropdown with 20 values (starting with the current year). The select values needed to be 2 digits and the display strings 4 digits. To avoid complex template code, I wrote this simple template tag:
@register.filter
def add_current_year(int_value, digits=4):
if digits == 2:
...
How to access pandas groupby dataframe by key
...t uses data-structures already available in the groupby object.
You can select different columns using the groupby slicing:
In [22]: gb[["A", "B"]].get_group("foo")
Out[22]:
A B
0 foo 1.624345
2 foo -0.528172
4 foo 0.865408
In [23]: gb["C"].get_group("foo")
Out[23]:
0 5
2 ...
invalid target release: 1.7
...ct JDK in your Maven run configuration. Go to Run -> Run Configuration, select your Maven Build configuration, go to JRE tab and set the correct Runtime JRE.
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Deprecated: mysql_connect()
... with @:
<?php
$connect = @mysql_connect('localhost','root','');
mysql_select_db('dbname');
?>
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Windows 7 SDK installation failure
...or modification.
Condition 1: If the Visual C++ Compilers checkbox is selected when the
Windows SDK 7.1 is installed, repaired, or modified after Visual
Studio 2010 SP1 has been installed, the error may be encountered and
some selected components may not be installed.
Workaround: Cl...
What is the best way to iterate over a dictionary?
...e wrong collection type in the first place), you should iterate dictionary.Select( (kvp, idx) => new {Index = idx, kvp.Key, kvp.Value}) instead and not use .ElementAt inside the loop.
– spender
Mar 2 '15 at 2:17
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Database development mistakes made by application developers [closed]
... the log output from Hibernate and you'll see all the queries begin with:
SELECT DISTINCT ...
This is a bit of a shortcut to ensuring you don't return duplicate rows and thus get duplicate objects. You'll sometimes see people doing this as well. If you see it too much it's a real red flag. Not...