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Why should we typedef a struct so often in C?
... x, int y);
and then provide the struct definition in the implementation file:
struct Point
{
int x, y;
};
Point * point_new(int x, int y)
{
Point *p;
if((p = malloc(sizeof *p)) != NULL)
{
p->x = x;
p->y = y;
}
return p;
}
In this latter case, you cannot return the Po...
PG undefinedtable error relation users does not exist
...l the migrations. It will only use the
contents of the current schema.rb file. If a migration can't be rolled back,
rake db:reset may not help you. To find out more about dumping the schema see
Schema Dumping and You section. Rails Docs
If the trick doesn't help, drop the database, then re-c...
How to get the number of days of difference between two dates on mysql?
...(md.end_date, md.start_date) AS days FROM membership_dates md
output::
id entity_id start_date end_date days
1 1236 2018-01-16 00:00:00 2018-08-31 00:00:00 227
2 2876 2015-06-26 00:00:00 2019-06-30 00:00:00 1465
3 3880 1990-06-05 00:0...
What is JNDI? What is its basic use? When is it used?
... so this is basically a safer alternative to having a properties file with your jdbc connection info?
– grinch
Jan 16 '14 at 18:13
4
...
Keyboard shortcut to change font size in Eclipse?
...t will be zoomed.
So, the font size change is not limited to the current file and the new value of the font size is available here Window > Preferences > General > Appearance > Colors and Fonts.
share
...
Class method differences in Python: bound, unbound and static
...t()
>>> a_test.method_two()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: method_two() takes no arguments (1 given)
You can change the behavior of a method using a decorator
class Test(object):
def method_one(self):
print "C...
How to keep a Python script output window open?
I have just started with Python. When I execute a python script file on Windows, the output window appears but instantaneously goes away. I need it to stay there so I can analyze my output. How can I keep it open?
...
Can you give a Django app a verbose name for use throughout the admin?
...was needed before Django 1.7. If you're using 1.7 or above, use an apps.py file as recommended below by iMaGiNiX.
– shacker
Feb 2 '15 at 22:40
|
...
Loop inside React JSX
...ows; i++) {
// note: we add a key prop here to allow react to uniquely identify each
// element in this array. see: https://reactjs.org/docs/lists-and-keys.html
rows.push(<ObjectRow key={i} />);
}
return <tbody>{rows}</tbody>;
Incidentally, my JavaScript example is al...
What are some (concrete) use-cases for metaclasses?
...ags etc) for its type. Adding a handler for a new type becomes:
class Mp3File(MusicFile):
extensions = ['.mp3'] # Register this type as a handler for mp3 files
...
# Implementation of mp3 methods go here
The metaclass then maintains a dictionary of {'.mp3' : MP3File, ... } etc, and ...