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super() raises “TypeError: must be type, not classobj” for new-style class
...super() cannot be used with an old-style class".
However, the important point is that the correct test for "is this a new-style instance (i.e. object)?" is
>>> class OldStyle: pass
>>> instance = OldStyle()
>>> issubclass(instance.__class__, object)
False
and not (as i...
Why doesn't std::queue::pop return value.?
... this scenario (with a naive/made up pop implementation, to ilustrate my point):
template<class T>
class queue {
T* elements;
std::size_t top_position;
// stuff here
T pop()
{
auto x = elements[top_position];
// TODO: call destructor for elements[top_positi...
using awk with column value conditions
...n this answer as it's using a string in a regexp context and so awk has to convert the string to a regexp before using it and that has side-effects (man awk).
– Ed Morton
Jun 30 '16 at 18:51
...
How to create hyperlink to call phone number on mobile devices?
...or this reason the + sign is always necessary. The + sign is automatically converted by your mobile carrier to your international dialing prefix, also known as "exit code". This code varies by region, country, and sometimes a single country can use multiple codes, depending on the carrier. Fortunate...
Android - Spacing between CheckBox and text
...DisplayMetrics().density;
checkBox.setPadding(checkBox.getPaddingLeft() + (int)(10.0f * scale + 0.5f),
checkBox.getPaddingTop(),
checkBox.getPaddingRight(),
checkBox.getPaddingBottom());
This gives you the following, where the green line is the increase in padding. This is...
When is “i += x” different from “i = i + x” in Python?
...s is why
i = 1
i += 1
seems to increment i. In reality, you get a new integer and assign it "on top of" i -- losing one reference to the old integer. In this case, i += 1 is exactly the same as i = i + 1. But, with most mutable objects, it's a different story:
As a concrete example:
a = [1,...
The specified type member 'Date' is not supported in LINQ to Entities. Only initializers, entity mem
...
DateTime.Date cannot be converted to SQL. Use EntityFunctions.TruncateTime method to get date part.
var eventsCustom = eventCustomRepository
.FindAllEventsCustomByUniqueStudentReference(userDevice.UniqueStudentReference)
.Where(x => EntityFuncti...
Testing if object is of generic type in C#
...t.GetType().GetGenericTypeDefinition() == typeof(List<>);
As Jon points out, this checks the exact type equivalence. Returning false doesn't necessarily mean list is List<T> returns false (i.e. the object cannot be assigned to a List<T> variable).
...
How can I tell jackson to ignore a property for which I don't have control over the source code?
...
You can use Jackson Mixins. For example:
class YourClass {
public int ignoreThis() { return 0; }
}
With this Mixin
abstract class MixIn {
@JsonIgnore abstract int ignoreThis(); // we don't need it!
}
With this:
objectMapper.getSerializationConfig().addMixInAnnotations(YourClas...
GUI-based or Web-based JSON editor that works like property explorer [closed]
...put a UI in front of the Perl data structure generation, e.g. a web form.
Converting a structure to JSON is very straightforward:
use strict;
use warnings;
use JSON::Any;
my $data = { arbitrary structure in here };
my $json_handler = JSON::Any->new(utf8=>1);
my $json_string = $json_handler-...