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(-2147483648> 0) returns true in C++?
... exponent part. An integer literal may have a prefix that specifies its
base and a suffix that specifies its type.
…
The type of an integer literal is the first of the corresponding list
in which its value can be represented.
If an integer literal cannot be represented by any t...
What are best practices for validating email addresses on iOS 2.0
...a-z0-9]+(-[a-z0-9]+)*\\.)+[a-z]{2,4}\\z";
NSString *regex2 = @"^(?=.{1,64}@.{4,64}$)(?=.{6,100}$).*";
NSPredicate *test1 = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex1];
NSPredicate *test2 = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex2];
return [test1 ev...
Evaluating a mathematical expression in a string
...might be possible to break out using introspection:
eval('(1).__class__.__bases__[0].__subclasses__()', {'__builtins__': None})
Evaluate arithmetic expression using ast
import ast
import operator as op
# supported operators
operators = {ast.Add: op.add, ast.Sub: op.sub, ast.Mult: op.mul,
...
Detecting endianness programmatically in a C++ program
...
I don't like the method based on type punning - it will often be warned against by compiler. That's exactly what unions are for !
bool is_big_endian(void)
{
union {
uint32_t i;
char c[4];
} bint = {0x01020304};
return b...
Is there a way to make mv create the directory to be moved to if it doesn't exist?
...
[ -a "$dir" ] ||
mkdir -p "$dir" &&
mv "$@"
}
These based on the submission of Chris Lutz.
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Best GWT widget library? [closed]
...framework (which may not be entirely compatible with the rest of your code base), or you have to adopt someone's new fangled layout system, or you have to live with the fact that you cannot really debug the code (because its just JSNI wrappers).
Don't get me wrong, the GWT Incubator isn't perfect.....
Groovy / grails how to determine a data type?
...
instanceof is great for filtering based on interface.
– cdeszaq
Mar 12 '13 at 13:15
...
How can I recall the argument of the previous bash command?
...
!!:n where n is the 0-based position of the argument you want.
For example:
echo 'one' 'two'
# "one two"
echo !!:2
# "two"
The ! prefix is used to access previous commands.
Other useful commands:
!$ - last argument from previous command
!^...
How to get device make and model on iOS?
...de objectForKey:code];
if (!deviceName) {
// Not found on database. At least guess main device type from string contents:
if ([code rangeOfString:@"iPod"].location != NSNotFound) {
deviceName = @"iPod Touch";
}
else if([code rangeOfString:@"iPad"].lo...
How do I write a short literal in C++?
...
Jonathan Leffler
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answered Oct 16 '08 at 13:01
Mike FM...