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differentiate null=True, blank=True in django
...o need your database to allow NULL values for that field. The exception is CharFields and TextFields, which in Django are never saved as NULL. Blank values are stored in the DB as an empty string ('').
A few examples:
models.DateTimeField(blank=True) # raises IntegrityError if blank
models.DateTi...
Are “while(true)” loops so bad? [closed]
...// do something with the line
}
And in C, it's
#include <stdio.h>
char* buffer = NULL;
size_t buffer_size;
size_t size_read;
while( (size_read = getline(&buffer, &buffer_size, stdin)) != -1 ){
// do something with the line
}
free(buffer);
or if you're convinced you know how long...
Why do we need argc while there is always a null at the end of argv?
...
...Which is a shame, in a way. If we had int main(char *argv[], int argc, ...), then some programs could just omit the argc because they do not need it. Opposite (needing argc but not argv) is probably never useful in a real program.
– hyde
...
Why does flowing off the end of a non-void function without returning a value not produce a compiler
...times it is wrong and you have to put in an unnecessary return statement.
char getChoice() {
int ch = read();
if (ch == -1 || ch == 'q') {
System.exit(0);
}
else {
return (char) ch;
}
// Cannot reach here, but still an error.
}
It's a philosophical differ...
How to implement an STL-style iterator and avoid common pitfalls?
...
http://www.cplusplus.com/reference/std/iterator/ has a handy chart that details the specs of § 24.2.2 of the C++11 standard. Basically, the iterators have tags that describe the valid operations, and the tags have a hierarchy. Below is purely symbolic, these classes don't actually e...
How to reuse an ostringstream?
...ct of the deprecated std::strstream, which was able to write directly to a char array you allocated on the stack. You had to insert a terminating null manually. However, std::ends is not deprecated, i think because it's still useful as in the above cases.
...
Linux: compute a single hash for a given folder & contents?
...
@RichardBronosky - Let us assume we have two files, A and B. A contains "foo" and B contains "bar was here". With your method, we would not be able to separate that from two files C and D, where C contains "foobar" and D contain...
How to make the 'cut' command treat same sequental delimiters as one?
... page:
-s, --squeeze-repeats replace each input sequence of a repeated character
that is listed in SET1 with a single occurrence
of that character
share
|
...
How to compute the similarity between two text documents?
...mmer = nltk.stem.porter.PorterStemmer()
remove_punctuation_map = dict((ord(char), None) for char in string.punctuation)
def stem_tokens(tokens):
return [stemmer.stem(item) for item in tokens]
'''remove punctuation, lowercase, stem'''
def normalize(text):
return stem_tokens(nltk.word_tokeni...
How does this milw0rm heap spraying exploit work?
...ely random. That cannot be right. I tried to swap bytes, assuming that the characters in a string were stored in little-endian, but it did not help.
– Juho Östman
Nov 17 '10 at 19:48
...