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Django: Get an object form the DB, or 'None' if nothing matches
...get(*args, **kwargs)
except model.DoesNotExist:
return None
Call it like this
foo = get_or_none(Foo, baz=bar)
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How can I beautify JavaScript code using Command Line?
...y-web/js-beautify/blob/master/js/lib/beautify.js
Second, download and install The Mozilla group's Java based Javascript engine, Rhino. "Install" is a little bit misleading; Download the zip file, extract everything, place js.jar in your Java classpath (or Library/Java/Extensions on OS X). You ca...
How do I clone a Django model instance object and save it to the database?
...
Just change the primary key of your object and run save().
obj = Foo.objects.get(pk=<some_existing_pk>)
obj.pk = None
obj.save()
If you want auto-generated key, set the new key to None.
More on UPDATE/INSERT here.
Official docs on copying model instances: https://docs.djangoproje...
Create directory if it does not exist
...
What will -Force actually do? The documentation says "Forces this cmdlet to create an item that writes over an existing read-only item". Will it delete an existing folder? It should be clear in this answer.
– Peter Mortensen...
What is the difference between a 'closure' and a 'lambda'?
... function definition is re-written as binding a lambda to a variable internally. In other languages, like Python, there are some (rather needless) distinctions between them, but they behave the same way otherwise.
A closure is any function which closes over the environment in which it was defined. ...
Prevent HTML5 video from being downloaded (right-click saved)?
...y to do it is to serve the video using HTTP Live Streaming. What it essentially does is chop up the video into chunks and serve it one after the other. This is how most streaming sites serve video. So even if you manage to Save As, you only save a chunk, not the whole video. It would take a bit more...
Should I make HTML Anchors with 'name' or 'id'?
...ne wants to refer to some part of a webpage with the " http://example.com/#foo " method, should one use
14 Answers
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How do I trim a file extension from a String in Java?
...have Apache Commons I/O already in your project, that's right. But if this all you need from it, you're adding (at least) 2.5 MB of dead weight to your project for something that can be easily done with a single line.
– foo
Sep 3 '18 at 9:40
...
while (1) Vs. for (;;) Is there a speed difference?
...p
.LCFI0:
movq %rsp, %rbp
.LCFI1:
.L2:
movl $.LC0, %edi
call puts
jmp .L2
.LFE2:
.size t_while, .-t_while
.globl t_for
.type t_for, @function
t_for:
.LFB3:
pushq %rbp
.LCFI2:
movq %rsp, %rbp
.LCFI3:
.L5:
movl $.LC0, %edi
call puts
j...
How to create file execute mode permissions in Git on Windows?
... would be nice if git-add had a --mode flag
git 2.9.x/2.10 (Q3 2016) actually will allow that (thanks to Edward Thomson):
git add --chmod=+x -- afile
git commit -m"Executable!"
That makes the all process quicker, and works even if core.filemode is set to false.
See commit 4e55ed3 (31 May 2016)...