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How to check for null in Twig?
...se (such as zero, empty string and empty array). Besides, it will cause an error if var is not defined. A safer way would be:
{% if var is not defined or var is null %}
which can be shortened to:
{% if var|default is null %}
If you don't provide an argument to the default filter, it assumes NU...
How do I prevent site scraping? [closed]
... proxy servers and VPNs, you will negatively affect real users.
Make your error message nondescript if you do block
If you do block / limit access, you should ensure that you don't tell the scraper what caused the block, thereby giving them clues as to how to fix their scraper. So a bad idea would...
Best way to give a variable a default value (simulate Perl ||, ||= )
... to do $var = @$var ?: 'default value'; If so, why? Given that the only "error" could be that $var isn't set, and that we don't care if $var isn't set...
– Codemonkey
Nov 13 '15 at 14:14
...
C# equivalent of the IsNull() function in SQL Server
... I tried to use the null-coalescing operator but kept getting the error Operator '??' cannot be applied to operands of type 'bool?' and 'int'. The error was misleading. The problem was that I was trying to assign a an int in the right-hand operand position to a boolean variable. I had to ch...
How to get a microtime in Node.js?
...* 1000000 + hrTime[1] / 1000)
(Thanks to itaifrenkel for pointing out an error in the conversion above.)
In modern browsers, time with microsecond precision is available as performance.now. See https://developer.mozilla.org/en-US/docs/Web/API/Performance/now for documentation.
I've made an imple...
Is there a way to make R beep/play a sound at the end of a script?
...ge has a lot of visibility: can beepr be called from options, i.e. options(error=beepr(sound=9)) ? Calling it after a successful run is useful U& i'll use it, but also it'd be great to call it if the code crashes... Cheers!
– dez93_2000
Sep 2 '14 at 22:09
...
Why is this jQuery click function not working?
...-up overlays and then spent several frustrating hours looking for a script error. Big lesson learnt.
– johnlholden
May 7 '14 at 14:57
...
T-SQL: Deleting all duplicate rows but keeping one [duplicate]
...
Using this format I got the following error, any ideas? "ERROR 1093 (HY000): You can't specify target table 'Table' for update in FROM clause"
– M1ke
Aug 23 '13 at 11:24
...
How to validate a url in Python? (Malformed or not)
...alidators import URLValidator
from django.core.exceptions import ValidationError
val = URLValidator(verify_exists=False)
try:
val('http://www.google.com')
except ValidationError, e:
print e
If you set verify_exists to True, it will actually verify that the URL exists, otherwise it will ju...
TypeError: not all arguments converted during string formatting python
...
The error is in your string formatting.
The correct way to use traditional string formatting using the '%' operator is to use a printf-style format string (Python documentation for this here: http://docs.python.org/2/library/str...