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How do I filter ForeignKey choices in a Django ModelForm?
... @Slott cheers, I've added an answer as it'd take more than 600 chars to explain . Even if this question is old it's getting a high google score.
– michael
Aug 7 '09 at 13:19
...
Search an Oracle database for tables with specific column names?
...'CLOB',null,'NUMBER',
decode(data_precision,null,to_char(data_length),
data_precision||','||data_scale
), data_length
) || ')' data_type
from all_tab_columns
where column_name like ('%' || uppe...
What does the @ symbol represent in objective-c?
...
The @ character isn't used in C or C++ identifiers, so it's used to introduce Objective-C language keywords in a way that won't conflict with the other languages' keywords. This enables the "Objective" part of the language to free...
How do I record audio on iPhone with AVAudioRecorder?
... code]);
NSLog(@"Error: %@ [%4.4s])" , [error localizedDescription], (char*)&errorCode);
}
NSLog(@"recording");
}
-(IBAction) stopRecording
{
NSLog(@"stopRecording");
[audioRecorder stop];
NSLog(@"stopped");
}
-(IBAction) playRecording
{
NSLog(@"playRecording");
// Init audio with playb...
Enums and Constants. Which to use when?
...ype. You can change the default from int to any other integral type except char like:
enum LongEnum : long {
foo,
bar,
}
You can cast explicitly from and implicitly to the the base type, which is useful in switch-statements. Beware that one can cast any value of the base type to an enum, ...
Difference between `const shared_ptr` and `shared_ptr`?
...);
sA->a = 4; // compile-error
return sA;
}
int main(int argc, char** argv) {
f1();
f2();
return 0;
}
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What is the difference between square brackets and parentheses in a regex?
...nt, you would code (?:7|8|9) to make it a non capturing group.
[abc] is a "character class" that means "any character from a,b or c" (a character class may use ranges, e.g. [a-d] = [abcd])
The reason these regexes are similar is that a character class is a shorthand for an "or" (but only for singl...
What is the difference between NULL, '\0' and 0?
...xDEADBEEF)
as these are seen by a compiler as normal comparisons.
Null Characters
'\0' is defined to be a null character - that is a character with all bits set to zero. This has nothing to do with pointers. However you may see something similar to this code:
if (!*string_pointer)
checks if ...
Soft wrap at 80 characters in Vim in window of arbitrary width
... to use Vim's soft wrap capability ( :set wrap ) to wrap some code at 80 characters, regardless of my actual window width.
...
How to send password securely over HTTP?
...ded using
the RFC2045-MIME variant of Base64, except not limited to 76
char/line.
The authorization method and a space i.e. "Basic " is then
put before the encoded string.
source: Wikipedia: Authorization header
It might seem a bit complicated, but it is not.
There are plenty go...