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How do I get the object if it exists, or None if it does not exist?
... SomeModel.objects.get(foo='bar')
except SomeModel.DoesNotExist:
go = None
What I did do, is to subclass models.Manager, create a safe_get like the code above and use that manager for my models. That way you can write: SomeModel.objects.safe_get(foo='bar').
...
How to delete a remote tag?
...
And just in case someone wonders how to delete multiple tags at a time you simple list them using white space, e.g. git push --delete origin tag1 tag2. Same is valid for local tags deletion git tag -d tag1 tag2
– dVaffection...
Catching java.lang.OutOfMemoryError?
... infrequently is OutOfMemoryError the death-knell to a JVM.
There is only one good reason to catch an OutOfMemoryError and that is to close down gracefully, cleanly releasing resources and logging the reason for the failure best you can (if it is still possible to do so).
In general, the OutOfMemo...
How can I nullify css property?
... Initial value : auto
Another example, max-height:
Initial value : none
In 2017, there is now another way, the unset keyword:
.c1 {
height: unset;
}
Some documentation: https://developer.mozilla.org/en-US/docs/Web/CSS/unset
The unset CSS keyword is the combination of the initia...
Doctrine 2 can't use nullable=false in manyToOne relation?
An User has one Package associated with it. Many users can refer to the same package. User cannot exists without a Package defined. User should own the relation. Relation is bidirectional, so a Package has zero or more users in it.
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Changing every value in a hash in Ruby
...swered Sep 4 '14 at 12:55
shock_oneshock_one
5,23722 gold badges2323 silver badges3434 bronze badges
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DistutilsOptionError: must supply either home or prefix/exec-prefix — not both
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good stuff, the link is bad, this is the new one I expect : github.com/Homebrew/homebrew/blob/master/share/doc/homebrew/…
– patt0
Nov 7 '14 at 7:54
...
How to log cron jobs?
...xecuted, which only logs IF the
cronjob TRIED to execute the command. That one is located in
/var/log/syslog, as already mentioned by @Matthew Lock.
The logging of errors AFTER the program tried to execute, which can be sent to
an email or to a file, as mentioned by @Spliffster. I prefer logging
to ...
How to silence output in a Bash script?
...og documenting &>s introduction? :o
– ThorSummoner
Mar 25 '15 at 21:40
1
git.savannah.gnu....
Heroku + node.js error (Web process failed to bind to $PORT within 60 seconds of launch)
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This answer is not only more complete, but the only one that targeted the two possible problems. In my case the port configuration was correct, but not the listening address. This should be the accepted answer.
– Danielo515
Feb 12 '18 at ...