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How do I add a placeholder on a CharField in Django?
...
Look at the widgets documentation. Basically it would look like:
q = forms.CharField(label='search',
widget=forms.TextInput(attrs={'placeholder': 'Search'}))
More writing, yes, but the separation allows for better abstraction of more complic...
How can I tell gcc not to inline a function?
Say I have this small function in a source file
8 Answers
8
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Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
Recommendations of Python REST (web services) framework? [closed]
...portant in REST, and unless you're very careful about this, you'll end up falling into a REST anti-pattern.
Some frameworks that get it right are web.py, Flask and Bottle. When combined with the mimerender library (full disclosure: I wrote it), they allow you to write nice RESTful webservices:
imp...
Should I use Vagrant or Docker for creating an isolated environment? [closed]
...I think Docker is what you want.
Vagrant is a virtual machine manager. It allows you to script the virtual machine configuration as well as the provisioning. However, it is still a virtual machine depending on VirtualBox (or others) with a huge overhead. It requires you to have a hard drive file th...
In which case do you use the JPA @JoinTable annotation?
... project_id
name name task_id
The Project_Tasks table is called a "Join Table". To implement this second solution in JPA you need to use the @JoinTable annotation. For example, in order to implement a uni-directional one-to-many association, we can define our entities as such:
Proj...
“Inner exception” (with traceback) in Python?
...recently started programming in Python. When an exception is thrown I typically want to wrap it in another exception that adds more information, while still showing the full stack trace. It's quite easy in C#, but how do I do it in Python?
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How can I open multiple files using “with open” in Python?
I want to change a couple of files at one time, iff I can write to all of them. I'm wondering if I somehow can combine the multiple open calls with the with statement:
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
...answered Dec 4 '13 at 19:36
Dan AllanDan Allan
27.4k66 gold badges6060 silver badges6060 bronze badges
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Capturing Groups From a Grep RegEx
...egex="[0-9]+_([a-z]+)_[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
...