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How to check for null in Twig?
... on what exactly you need:
is null checks whether the value is null:
{% if var is null %}
{# do something #}
{% endif %}
is defined checks whether the variable is defined:
{% if var is not defined %}
{# do something #}
{% endif %}
Additionally the is sameas test, which does a type st...
Django in / not in query
... Was trying to use this solution and ran into a problem, so if it happens to anyone else... Objs=Tbl1.objects.filter(...); IDs=Objs.values_list('id', flat=True); Objs.delete(); Tbl2.objects.filter(id__in=IDs') This did not work because IDs is actually a QuerySet object. When I deleted...
Generating v5 UUID. What is name and namespace?
...ducible UUID for each namespace using "uuid -v5 $ROOTUUID $NAMESPACENAME". Now you can create unique UUIDs for keys within a namespace using "uuid -v5 $NAMESPACEUUID $KEY". These UUIDs can be thrown into a single key-value store with high probability of avoiding collision. This process can be repea...
Versioning SQL Server database
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This is one of the "hard problems" surrounding development. As far as I know there are no perfect solutions.
If you only need to store the database structure and not the data you can export the database as SQL queries. (in Enterprise Manager: Right click on database -> Generate SQL script. I ...
What is WEB-INF used for in a Java EE web application?
...ld process.
While you are usually free to design your own build process, nowadays most people will use a standardized approach such as Apache Maven. Among other things Maven defines defaults for which resources in the project structure map to what resources in the resulting artifact (the resulting...
How to make a countdown timer in Android?
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What if I wanted to base the CountDownTimer on a set alarm? How do I know how many milisUntilFinished?
– Kala J
Nov 7 '14 at 12:54
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Check if event exists on element [duplicate]
Is there a way to check if an event exists in jQuery? I’m working on a plugin that uses custom namespaced events, and would like to be able to check if the event is binded to an element or not.
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Why does viewWillAppear not get called when an app comes back from the background?
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In swift 4.2 the notification name is now UIApplication.willEnterForegroundNotification and UIApplication.didBecomeActiveNotification
– hordurh
Oct 15 '18 at 15:08
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How to call base.base.method()?
...se to a question. It was asked for a reason, not a scolding. If you don't know, then don't answer it! I'd also like to encourage everyone to blast the code-police so maybe it will discourage them from posting non-answers. If after answering a question, you feel compelled to quote guidelines, then g...
Android: Difference between onInterceptTouchEvent and dispatchTouchEvent?
What is the difference between onInterceptTouchEvent and dispatchTouchEvent in Android?
14 Answers
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