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Argparse: Required arguments listed under “optional arguments”?
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Parameters starting with - or -- are usually considered optional. All other parameters are positional parameters and as such required by design (like positional function arguments). It is possible to require optional arguments, but this is a bit against their desig...
Getting current device language in iOS?
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The solutions provided will actually return the current region of the device - not the currently selected language. These are often one and the same. However, if I am in North America and I set my language to Japanese, my region will still be English (Unite...
Remove a string from the beginning of a string
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Plain form, without regex:
$prefix = 'bla_';
$str = 'bla_string_bla_bla_bla';
if (substr($str, 0, strlen($prefix)) == $prefix) {
$str = substr($str, strlen($prefix));
}
Takes: 0.0369 ms (0.000,036,954 seconds)
And with:
$prefix = 'bla_';
$str = 'bla_string...
UICollectionView reloadData not functioning properly in iOS 7
...nd probing. I feel this is an iOS 7 bug. Forcing the main thread will run all UIKit related messages. I seem to run into this when popping to the view from another view controller. I refresh the data on viewWillAppear. I could see the data and collection view reload call, but the UI was not updat...
What is the maximum float in Python?
I think the maximum integer in python is available by calling sys.maxint .
3 Answers
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Will strlen be calculated multiple times if used in a loop condition?
...optimiser might be able to deduce that the value won't change, but I personally wouldn't rely on that.
I'd do something like
for (int i = 0, n = strlen(ss); i < n; ++i)
or possibly
for (int i = 0; ss[i]; ++i)
as long as the string isn't going to change length during the iteration. If it mi...
What do “branch”, “tag” and “trunk” mean in Subversion repositories?
...ode in the trunk. If the major changes work according to plan, they are usually merged back into the trunk.
Tag will be a point in time on the trunk or a branch that you wish to preserve. The two main reasons for preservation would be that either this is a major release of the software, whether alp...
SQL Server indexes - ascending or descending, what difference does it make?
...ces to rows.
Since the table is clustered, the references to rows are actually the values of the pk. They are also ordered within each value of col1.
This means that that leaves of the index are actually ordered on (col1, pk), and this query:
SELECT col1, pk
FROM mytable
ORDER BY
col1...
Difference between fprintf, printf and sprintf?
...on>
#include <stdarg.h>
#include <stdio.h>
struct exception_fmt : std::exception
{
exception_fmt(char const* fmt, ...) __attribute__ ((format(printf,2,3)));
char const* what() const throw() { return msg_; }
char msg_[0x800];
};
exception_fmt::exception_fmt(char const* fm...
How to list the tables in a SQLite database file that was opened with ATTACH?
....schema tablename
Print the entire table:
SELECT * FROM tablename;
List all of the available SQLite prompt commands:
.help
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