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Define make variable at rule execution time
...te a unique variable, you could do the following:
out.tar :
$(eval $@_TMP := $(shell mktemp -d))
@echo hi $($@_TMP)/hi.txt
tar -C $($@_TMP) cf $@ .
rm -rf $($@_TMP)
This would prepend the name of the target (out.tar, in this case) to the variable, producing a variable with the na...
How much is the overhead of smart pointers compared to normal pointers in C++?
...
std::unique_ptr has memory overhead only if you provide it with some non-trivial deleter.
std::shared_ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constru...
Using pickle.dump - TypeError: must be str, not bytes
..., that's why you are here.
import pickle
class MyUser(object):
def __init__(self,name):
self.name = name
user = MyUser('Peter')
print("Before serialization: ")
print(user.name)
print("------------")
serialized = pickle.dumps(user)
filename = 'serialized.native'
with open(filename,...
Difference between staticmethod and classmethod
... code will help: Notice the difference in the call signatures of foo, class_foo and static_foo:
class A(object):
def foo(self, x):
print "executing foo(%s, %s)" % (self, x)
@classmethod
def class_foo(cls, x):
print "executing class_foo(%s, %s)" % (cls, x)
@staticme...
Do declared properties require a corresponding instance variable?
...String *name;
it will generate synthesizing code as
@synthesize name = _name;
and you can access instance variable using _name
it is similar to declare
NSString* _name
but if you declare read-only property it like
@property (nonatomic, strong, readonly) NSString *name;
it will generate ...
Python 3 turn range to a list
...
You can just construct a list from the range object:
my_list = list(range(1, 1001))
This is how you do it with generators in python2.x as well. Typically speaking, you probably don't need a list though since you can come by the value of my_list[i] more efficiently (i + 1), and...
What is the most efficient way to store a list in the Django models?
...
See docs.djangoproject.com/en/3.0/topics/db/examples/many_to_one
– Jon Ison
Jul 2 at 9:42
...
Mixin vs inheritance
...dited Jun 21 at 11:36
underscore_d
4,91633 gold badges2828 silver badges5454 bronze badges
answered May 13 '09 at 20:42
...
Fast Linux File Count for a large number of files
...lly, the system shouldn't allow any path name that is longer than than PATH_MAX. If there are concerns, I can fix that, but it's just more code that needs to be explained to someone learning to write C. This program is intended to be an example of how to dive into subdirectories recursively.
#inclu...
Remove all special characters with RegExp
...d of ^\w. \W : Matches any non-word character. Equivalent to [^A-Za-z0-9_]. developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/…
– delkant
Jun 24 '16 at 22:14
...