大约有 40,000 项符合查询结果（耗时：0.0322秒） [XML]
What is the fastest way to check if a class has a function defined?
...tr() to get the attribute, and callable() to verify it is a method:
invert_op = getattr(self, "invert_op", None)
if callable(invert_op):
invert_op(self.path.parent_op)
Note that getattr() normally throws exception when the attribute doesn't exist. However, if you specify a default value (None...
Interfacing with structs and anonymous unions with c2hs
...You would have to do this patch for each version of the lib.
struct monome_event {
monome_t *monome;
monome_event_type_t event_type;
/* __extension__ for anonymous unions in gcc */
__extension__ union {
struct me_grid {
unsigned int x;
unsigned int y...
How to search a specific value in all tables (PostgreSQL)?
...
How about dumping the contents of the database, then using grep?
$ pg_dump --data-only --inserts -U postgres your-db-name > a.tmp
$ grep United a.tmp
INSERT INTO countries VALUES ('US', 'United States');
INSERT INTO countries VALUES ('GB', 'United Kingdom');
The same utility, pg_dump, can...
unbound method f() must be called with fibo_ instance as first argument (got classobj instance inste
...thod() to access parent methods.
class ParentClass(object):
def method_to_call(self, arg_1):
print arg_1
class ChildClass(ParentClass):
def do_thing(self):
super(ChildClass, self).method_to_call('my arg')
...
What is the command to list the available avdnames
...ators: emulator @name-of-your-emulator where emulator is under: ${ANDROID_SDK}/tools/emulator
– Dhiraj Himani
Jun 16 '17 at 11:27
...
Flex-box: Align last row to grid
...p:wrap;
}
.grid::after{
content: '';
width: 10em // Same width of .grid__element
}
.grid__element{
width:10em;
}
With the HTML like this:
<div class=grid">
<div class="grid__element"></div>
<div class="grid__element"></div>
<div class="grid__elemen...
Extracting bits with a single multiplication
...and, namely SMT-LIB 2 input:
(set-logic BV)
(declare-const mask (_ BitVec 64))
(declare-const multiplicand (_ BitVec 64))
(assert
(forall ((x (_ BitVec 64)))
(let ((y (bvmul (bvand mask x) multiplicand)))
(and
(= ((_ extract 63 63) x) ((_ extract 63 63) y))
(= ...
powershell - extract file name and extension
... select -ExpandProperty value
$b | % {"File name:{0} - Extension:{1}" -f $_.substring(0, $_.lastindexof('.')) , $_.substring($_.lastindexof('.'), ($_.length - $_.lastindexof('.'))) }
If is a file you can use something like this based on your needs:
$a = dir .\my.file.xlsx # or $a = get-item c:\m...
Double Negation in C++
...ernel). For GCC, they're implemented as follows:
#define likely(cond) (__builtin_expect(!!(cond), 1))
#define unlikely(cond) (__builtin_expect(!!(cond), 0))
Why do they have to do this? GCC's __builtin_expect treats its parameters as long and not bool, so there needs to be some form of conver...
Getter and Setter declaration in .NET [duplicate]
...ed property. When the need arises you can expand your property to:
string _myProperty;
public string MyProperty
{
get { return _myProperty; }
set { _myProperty = value; }
}
Now you can add code that validates the value in your setter:
set
{
if (string.IsNullOrWhiteSpace(value))
...