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find vs find_by vs where
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Use whichever one you feel suits your needs best.
The find method is usually used to retrieve a row by ID:
Model.find(1)
It's worth noting that find will throw an exception if the item is not found by the attribute that you supply. Use where (as described below, which will return an empty arr...
Comma in C/C++ macro
...his is also a problem for square brackets and braces, even though those usually occur as balanced pairs.) You can enclose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remains parenthesized inside the macro expansion, which pr...
How does JavaScript .prototype work?
...ing languages but I've written my fair share of JavaScript code. I never really got my head around this prototype-based programming, does any one know how this works?
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Kotlin secondary constructor
...tructors in Kotlin since these constructors are necessary sometimes, especially when working with Java frameworks and extending Java classes. Hope you'll get them back soon.
– Michael
Jul 17 '14 at 7:46
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Get all related Django model objects
How can I get a list of all the model objects that have a ForeignKey pointing to an object? (Something like the delete confirmation page in the Django admin before DELETE CASCADE).
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Disable assertions in Python
...trate each.
For the whole process
Using the -O flag (capital O) disables all assert statements in a process.
For example:
$ python -Oc "assert False"
$ python -c "assert False"
Traceback (most recent call last):
File "<string>", line 1, in <module>
AssertionError
Note that by di...
How to open multiple pull requests on GitHub
When I open a pull request on GitHub .
All commits since my last request and all new ones are automatically added to this request .
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Django, creating a custom 500/404 error page
... for some reason request.user appears fine in the 404 template, but not at all in the 500 template (and they are almost identical) -- posted question on this here: stackoverflow.com/questions/26043211/…
– Gravity Grave
Sep 25 '14 at 16:13
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What do the terms “CPU bound” and “I/O bound” mean?
...U (doing calculations). A program that computes new digits of π will typically be CPU-bound, it's just crunching numbers.
A program is I/O bound if it would go faster if the I/O subsystem was faster. Which exact I/O system is meant can vary; I typically associate it with disk, but of course networ...
Django : How can I see a list of urlpatterns?
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If you want a list of all the urls in your project, first you need to install django-extensions, add it to your settings like this:
INSTALLED_APPS = (
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'django_extensions',
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)
And then, run this command in your terminal
./manage.py show_...