大约有 30,000 项符合查询结果（耗时：0.0269秒） [XML]
Do I need to explicitly call the base virtual destructor?
...of concept with results:
class base {
public:
base() { cout << __FUNCTION__ << endl; }
~base() { cout << __FUNCTION__ << endl; }
};
class derived : public base {
public:
derived() { cout << __FUNCTION__ << endl; }
~derived() { cout << __FU...
In a django model custom save() method, how should you identify a new object?
...eld.
– Dave W. Smith
Aug 9 '16 at 2:32
|
show 6 more comments
...
Eclipse executable launcher error: Unable to locate companion shared library
...
on XP 32 bit I had to: Move the zip file to the root. Rename it to e.zip. Open in it in 7Zip and rename the "eclipse" folder in there to "e". Unzip it - rename the extracted folder to "eclipse". Bonkers.
– Red...
Elegant Python function to convert CamelCase to snake_case?
...se
import re
name = 'CamelCaseName'
name = re.sub(r'(?<!^)(?=[A-Z])', '_', name).lower()
print(name) # camel_case_name
If you do this many times and the above is slow, compile the regex beforehand:
pattern = re.compile(r'(?<!^)(?=[A-Z])')
name = pattern.sub('_', name).lower()
To handle mor...
Add Foreign Key to existing table
...
To add a foreign key (grade_id) to an existing table (users), follow the following steps:
ALTER TABLE users ADD grade_id SMALLINT UNSIGNED NOT NULL DEFAULT 0;
ALTER TABLE users ADD CONSTRAINT fk_grade_id FOREIGN KEY (grade_id) REFERENCES grades(id);
...
Unexpected results when working with very big integers on interpreted languages
... which supports arbitrary precision. It will produce the correct answer on 32 or 64 bit platforms.
This can be seen by raising 2 to a power far greater than the bit width of the platform:
>>> 2**99
633825300114114700748351602688L
You can demonstrate (with Python) that the erroneous val...
How do I determine the size of an object in Python?
...>>> sys.getsizeof(x)
24
>>> sys.getsizeof(sys.getsizeof)
32
>>> sys.getsizeof('this')
38
>>> sys.getsizeof('this also')
48
If you are in python < 2.6 and don't have sys.getsizeof you can use this extensive module instead. Never used it though.
...
Limits of Nat type in Shapeless
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
Getting an “ambiguous redirect” error
...
ghostdog74ghostdog74
269k4848 gold badges233233 silver badges323323 bronze badges
1
...
Getting name of windows computer running python script?
...hon scrips are for sure running on a windows system, you should use the Win32 API GetComputerName or GetComputerNameEx
You can get the fully qualified DNS name, or NETBIOS name, or a variety of different things.
import win32api
win32api.GetComputerName()
>>'MYNAME'
Or:
import win32api
WI...