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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...ace and for every LongNamedRestaurant. LongNamedRestaurant just creates an extra table with the food_type and a reference to the place table.
If you do Place.objects.all(), you also get every place that is a LongNamedRestaurant, and it will be an instance of Place (without the food_type). So Place....
const char * const versus const char *?
...
The latter prevents you from modifying the_string inside print_string. It would actually be appropriate here, but perhaps the verbosity put off the developer.
char* the_string : I can change which char the_string points to, and I can modify the char to which it points...
Get fully qualified class name of an object in Python
...
Here's one based on Greg Bacon's excellent answer, but with a couple of extra checks:
__module__ can be None (according to the docs), and also for a type like str it can be __builtin__ (which you might not want appearing in logs or whatever). The following checks for both those possibilities:
...
What is the difference between up-casting and down-casting with respect to class variable
...og.
Police Dog - Police Dog extends Pet Dog.
public class Dog{
public String getType () {
System.out.println("NormalDog");
return "NormalDog";
}
}
/**
* Pet Dog has an extra method dogName()
*/
public class PetDog extends Dog{
public String getType () {
System.ou...
Rotate axis text in python matplotlib
...irst to assign the labels,
# otherwise get_xticklabels() will return empty strings.
plt.draw()
ax.set_xticklabels(ax.get_xticklabels(), rotation=45, ha='right')
Option 4
Similar to above, but loop through manually instead.
for label in ax.get_xticklabels():
label.set_rotation(45)
label.set_h...
Efficiency of Java “Double Brace Initialization”?
...Just for reference, double brace initialization is the following:
List<String> list = new ArrayList<String>() {{
add("Hello");
add("World!");
}};
It looks like a "hidden" feature of Java, but it is just a rewrite of:
List<String> list = new ArrayList<String>() {
...
Forced naming of parameters in Python
...ed.
Cons:
Checking occurs during run-time, not compile-time.
Use of an extra parameter (though not argument) and an additional check. Small performance degradation respect to regular functions.
Functionality is a hack without direct support by the language (see note below).
When calling the fun...
Visualizing branch topology in Git
...
Might I ask where you got the format string from? Or how on earth you concocted that thing?
– elliotwesoff
Oct 6 '16 at 16:38
...
Merge 2 arrays of objects
...mplexity as @YOU's answer, except that this is much slower (largely due to extra function calls and the fact the YOU's answer exploits the JS associative arrays trick to find items with O(1) lookup). This is besides the fact that you need to bring an additional library.
– Mrch...
How do I access the request object or any other variable in a form's clean() method?
...y.
A much better way is to override the form's __init__ method to take an extra keyword argument, request. This stores the request in the form, where it's required, and from where you can access it in your clean method.
class MyForm(forms.Form):
def __init__(self, *args, **kwargs):
se...