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How to invoke the super constructor in Python?
...on-3.x the process has been simplified:
Python-2.x
class A(object):
def __init__(self):
print "world"
class B(A):
def __init__(self):
print "hello"
super(B, self).__init__()
Python-3.x
class A(object):
def __init__(self):
print("world")
class B(A):
def __init__(self):
print...
How to create a custom string representation for a class object?
...
Implement __str__() or __repr__() in the class's metaclass.
class MC(type):
def __repr__(self):
return 'Wahaha!'
class C(object):
__metaclass__ = MC
print C
Use __str__ if you mean a readable stringification, use __repr__ fo...
String concatenation in Ruby
...; but that is not the usual way
With string interpolation
source = "#{ROOT_DIR}/#{project}/App.config"
with +
source = "#{ROOT_DIR}/" + project + "/App.config"
The second method seems to be more efficient in term of memory/speed from what I've seen (not measured though). All three methods will...
Grid of responsive squares
...isplay: flex;
flex-wrap: wrap;
justify-content: center;
}
.square-grid__cell {
background-color: rgba(0, 0, 0, 0.03);
box-shadow: 0 0 0 1px black;
overflow: hidden;
position: relative;
}
.square-grid__content {
left: 0;
position: absolute;
top: 0;
}
.square-grid__cell:after {
...
Django “xxxxxx Object” display customization in admin action sidebar
...
__unicode__ does do that. Your model should look something like this:
class SomeModel(models.Model):
def __unicode__(self):
return 'Policy: ' + self.name
On Python 3 you need to use __str__:
def __str__(self):
...
What are the mechanics of short string optimization in libc++?
...
The libc++ basic_string is designed to have a sizeof 3 words on all architectures, where sizeof(word) == sizeof(void*). You have correctly dissected the long/short flag, and the size field in the short form.
what value would __min_cap, ...
Calling class staticmethod within the class body?
...
staticmethod objects apparently have a __func__ attribute storing the original raw function (makes sense that they had to). So this will work:
class Klass(object):
@staticmethod # use as decorator
def stat_func():
return 42
_ANS = stat_func...
Multiple levels of 'collection.defaultdict' in Python
... @ScienceFriction Anything specific that you need help with? When d[new_key] is accessed, it will call the lambda which will create a new defaultdict(int). And when d[existing_key][new_key2] is accessed, a new int will be created.
– interjay
Oct 11 '13 at 1...
How is __eq__ handled in Python and in what order?
...
The a == b expression invokes A.__eq__, since it exists. Its code includes self.value == other. Since int's don't know how to compare themselves to B's, Python tries invoking B.__eq__ to see if it knows how to compare itself to an int.
If you amend your ...
print call stack in C or C++
...ing stack frame). To translate these to something of use, there's backtrace_symbols(3).
Pay attention to the notes section in backtrace(3):
The symbol names may be unavailable
without the use of special linker
options.
For systems using the GNU linker, it is necessary to use the
...