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Is there a way to instantiate objects from a string holding their class name?
...initializing or assigning to it. Have a look at its documentation here. Finally, the use of a raw function pointer is also a bit oldish. Modern C++ code should be decoupled from specific functions / types. You may want to look into Boost.Function to look for a better way. It would look like this the...
In Django, how do I check if a user is in a certain group?
...add(group) # user is now in the "Editor" group
then user.groups.all() returns [<Group: Editor>].
Alternatively, and more directly, you can check if a a user is in a group by:
if django_user.groups.filter(name = groupname).exists():
...
Note that groupname can also be the ac...
How to sort an IEnumerable
How can I sort an IEnumerable<string> alphabetically. Is this possible?
4 Answers
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'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
...
and tests whether both expressions are logically True while & (when used with True/False values) tests if both are True.
In Python, empty built-in objects are typically treated as logically False while non-empty built-ins are logically True. This facilitates the c...
What is the difference between AF_INET and PF_INET in socket programming?
... to do is to use AF_INET in your
struct sockaddr_in and PF_INET in your call to socket(). But
practically speaking, you can use AF_INET everywhere. And, since
that's what W. Richard Stevens does in his book, that's what I'll do
here.
...
Is there a MySQL option/feature to track history of changes to records?
...ant to audit the changes to the data - who did what and when?", you can usually use audit tables (as per the trigger example Keethanjan posted). I'm not a huge fan of triggers, but it has the great benefit of being relatively painless to implement - your existing code doesn't need to know about the ...
Quick easy way to migrate SQLite3 to MySQL? [closed]
...y's built a solid library that can convert between the two.
Here a list of ALL the differences in SQL syntax that I know about between the two file formats:
The lines starting with:
BEGIN TRANSACTION
COMMIT
sqlite_sequence
CREATE UNIQUE INDEX
are not used in MySQL
SQLite uses CREATE TABLE/INSERT ...
Can I change the checkbox size using CSS?
...ers no solutions in many cases (no solution to firefox on xp? no chrome at all?), is outdated and only contains a link and a comment of not much value.
– nurettin
Feb 13 '13 at 15:34
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Detect URLs in text with JavaScript
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Finally a regex that really works in most obvious case! This one deserves a bookmarking. I tested thousands examples from googles search until i find this.
– Ismael
Jan 16 '15 at 15:11
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Objective-C and Swift URL encoding
...ww";
NSString *escapedString = [unescaped stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLHostAllowedCharacterSet]];
NSLog(@"escapedString: %@", escapedString);
NSLog output:
escapedString: http%3A%2F%2Fwww
The following are useful URL encoding character sets:
URLFragm...