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Can I use a function for a default value in MySql?
... update previously existing rows, like this:
UPDATE app_users SET uuid = (SELECT uuid());
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Convert a string representation of a hex dump to a byte array using Java?
...;
for (int i = 0; i < len; i += 2) {
data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+ Character.digit(s.charAt(i+1), 16));
}
return data;
}
Reasons why it is an improvement:
Safe with leading zeros (unlike BigInteger) and wit...
Is there a simple way to convert C++ enum to string?
...
Excellent! Worked as a charm with a simple python script. Thanks.
– Edu Felipe
Oct 14 '08 at 19:43
6
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Coding Practices which enable the compiler/optimizer to make a faster program
...w customer\n"
"3) Destroy\n"
"4) Launch Nasal Demons\n"
"Enter selection: ";
static const size_t Menu_Text_Length = sizeof(Menu_Text) - sizeof('\0');
//...
std::cout.write(Menu_Text, Menu_Text_Length);
The efficiency of this technique can be visually demonstrated. :-)
Don't use print...
How to remove first 10 characters from a string?
How to ignore the first 10 characters of a string?
12 Answers
12
...
How to print a int64_t type in C
...t:
#include <stdio.h>
#include <stdint.h>
int main(int argc, char *argv[])
{
int64_t a = 1LL << 63;
uint64_t b = 1ULL << 63;
printf("a=%jd (0x%jx)\n", a, a);
printf("b=%ju (0x%jx)\n", b, b);
return 0;
}
Compiling this code with gcc -Wall -pedantic -...
Objective-C formatting string for boolean?
...
In Objective-C, the BOOL type is just a signed char. From <objc/objc.h>:
typedef signed char BOOL;
#define YES (BOOL)1
#define NO (BOOL)0
So you can print them using the %d formatter But that will only print a 1 or a 0, not YES or NO.
Or you can...
How to determine if a string is a number with C++?
...nt way would be just to iterate over the string until you find a non-digit character. If there are any non-digit characters, you can consider the string not a number.
bool is_number(const std::string& s)
{
std::string::const_iterator it = s.begin();
while (it != s.end() && std:...
Case objects vs Enumerations in Scala
...B', 3)
, KNIGHT('N', 3)
, ROOK('R', 5)
, PAWN('P', 1)
;
private char character;
private int pointValue;
private ChessPiece(char character, int pointValue) {
this.character = character;
this.pointValue = pointValue;
}
public int getCharacter() {
return character;
...
How does `is_base_of` work?
...;B, D>&)
D* (Host<B, D>&)
This would mean that we can't select by constness anymore. In an ordinary overload resolution scenario, the call would now be ambiguous because normally the return type won't participate in overload resolution. For conversion functions, however, there is ...