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Which is faster : if (bool) or if(int)?
... @Nathan: No. C++ has no bit data types. The smallest type is char, which is a byte by definition, and is the smallest addressable unit. bool's size is implementation-defined, and may be 1, 4, or 8, or whatever. Compilers tend to make it one, though.
– GManNickG
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What is the MySQL VARCHAR max size?
I would like to know what the max size is for a MySQL VARCHAR type.
7 Answers
7
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What breaking changes are introduced in C++11?
...hose for others to elaborate on.
Core language
#define u8 "abc"
const char *s = u8"def"; // Previously "abcdef", now "def"
#define _x "there"
"hello"_x // now a user-defined-string-literal. Previously, expanded _x .
New keywords: alignas, alignof, char16_t, char32_t, constexpr, declt...
How to delete duplicate lines in a file without sorting it in Unix?
... <sniff> makes me sad. ;) Anyways, [ -~] represents a range of ASCII characters from 0x20 (space) to 0x7E (tilde). These are considered the printable ASCII characters (linked page also has 0x7F/delete but that doesn't seem right). That makes the solution broken for anyone not using ASCII or an...
Regex doesn't work in String.matches()
...wercase letters, you can use .matches(), but you need to match one or more characters: append a + to your character class, as in [a-z]+. Or use ^[a-z]+$ and .find().
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Check if a String contains numbers Java
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To explain: .* means any character from 0 to infinite occurence, than the \\d+ (double backslash I think is just to escape the second backslash) and \d+ means a digit from 1 time to infinite.
– Giudark
Sep 29 '1...
Are HLists nothing more than a convoluted way of writing tuples?
...provides a form of polymorphic function value which allows the compiler to select type-specific cases in exactly the way you're doubtful about. For instance,
// size is a function from values of arbitrary type to a 'size' which is
// defined via type specific cases
object size extends Poly1 {
imp...
Get the current time in C
... by now, but you would use the strptime function in time.h to convert from char * to struct tm
– KingRadical
Nov 5 '13 at 19:59
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Generate a Hash from string in Javascript
...= 0, i, chr;
for (i = 0; i < this.length; i++) {
chr = this.charCodeAt(i);
hash = ((hash << 5) - hash) + chr;
hash |= 0; // Convert to 32bit integer
}
return hash;
}
});
Source:
http://werxltd.com/wp/2010/05/13/javascript-implementation-of-javas-string-h...
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...