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Which regular expression operator means 'Don't' match this character?
...ch a, b, c or 0: [^a-c0]
The latter: match any three-letter string except foo and bar:
(?!foo|bar).{3}
or
.{3}(?<!foo|bar)
Also, a correction for you: *, ? and + do not actually match anything. They are repetition operators, and always follow a matching operator. Thus, a+ means match one or ...
Django: Get an object form the DB, or 'None' if nothing matches
...
There are two ways to do this;
try:
foo = Foo.objects.get(bar=baz)
except model.DoesNotExist:
foo = None
Or you can use a wrapper:
def get_or_none(model, *args, **kwargs):
try:
return model.objects.get(*args, **kwargs)
except model.DoesNo...
ASP.NET MVC: Custom Validation by DataAnnotation
...ength(20, "Bar", "Baz", ErrorMessage = "The combined minimum length of the Foo, Bar and Baz properties should be longer than 20")]
public string Foo { get; set; }
public string Bar { get; set; }
public string Baz { get; set; }
}
...
Get name of object or class
...ill return empty string, if used on objects declared through variable: var Foo = function() {};.
– Aleksandr Makov
Feb 26 '14 at 14:56
3
...
Can you make just part of a regex case-insensitive?
...
@NonaUrbiz: Because the expression (?i)foobar is more readable than [Ff][Oo]{2}[Bb][Aa][Rr]
– Thanatos
Oct 25 '12 at 0:29
1
...
What is the “volatile” keyword used for?
...e visible to other processors.
Consider the following example:
something.foo = new Thing();
If foo is a member variable in a class, and other CPUs have access to the object instance referred to by something, they might see the value foo change before the memory writes in the Thing constructor ar...
If table exists drop table then create it, if it does not exist just create it
...
Just use DROP TABLE IF EXISTS:
DROP TABLE IF EXISTS `foo`;
CREATE TABLE `foo` ( ... );
Try searching the MySQL documentation first if you have any other problems.
share
|
imp...
Constructor of an abstract class in C#
...
From a terminology perspective, if Foo is an inheritable concrete type, and DerivedFoo:Foo, what term would you use to describe a heap object instance which will report its type as Foo, as distinct from DerivedFoo? My own inclination would be to use the phras...
class method generates “TypeError: … got multiple values for keyword argument …”
... is called, typically labelled self. If the class is declared thus:
class foo(object):
def foodo(self, thing=None, thong='not underwear'):
print thing if thing else "nothing"
print 'a thong is',thong
it behaves as expected.
Explanation:
Without self as the first parameter, when myfo...
How to create id with AUTO_INCREMENT on Oracle?
...asier to handle in some languages.
x is the identity column. Substitute FOO with your table name in each of the examples.
-- numerical identity, e.g. 1,2,3...
create table FOO (
x number primary key
);
create sequence FOO_seq;
create or replace trigger FOO_trg
before insert on FOO
for each...