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Better way to check variable for null or empty string?
... what is the purpose of !isset() here? how is it different to is_null()?
– nickf
May 7 '10 at 13:44
2
...
Using Django time/date widgets in custom form
... the proper field names from your model):
from django import forms
from my_app.models import Product
from django.contrib.admin import widgets
class ProductForm(forms.ModelForm):
class Meta:
model = Product
def __init__(self, *args, **kwargs):
...
What is a regular expression which will match a valid domain name without a subdomain?
...many valid edge cases that I have missed):
^((?!-))(xn--)?[a-z0-9][a-z0-9-_]{0,61}[a-z0-9]{0,1}\.(xn--)?([a-z0-9\-]{1,61}|[a-z0-9-]{1,30}\.[a-z]{2,})$
When choosing a domain validation regex, you should see if the domain matches the following:
xn--stackoverflow.com
stackoverflow.xn--com
stackov...
SQLAlchemy: print the actual query
...itting DDL. In order to access this functionality one can use the 'literal_binds' flag, passed to compile_kwargs:
from sqlalchemy.sql import table, column, select
t = table('t', column('x'))
s = select([t]).where(t.c.x == 5)
print(s.compile(compile_kwargs={"literal_binds": True}))
the above app...
How to add a new method to a php object on the fly?
...
You can harness __call for this:
class Foo
{
public function __call($method, $args)
{
if (isset($this->$method)) {
$func = $this->$method;
return call_user_func_array($func, $args);
}
...
Specifying an Index (Non-Unique Key) Using JPA
...Table;
@Entity
@Table(name = "region",
indexes = {@Index(name = "my_index_name", columnList="iso_code", unique = true),
@Index(name = "my_index_name2", columnList="name", unique = false)})
public class Region{
@Column(name = "iso_code", nullable = false)
priva...
How to check if a table contains an element in Lua?
...
Perhaps also function keysOfSet(set) local ret={} for k,_ in pairs(set) do ret[#ret+1]=k end return ret end
– Jesse Chisholm
Apr 27 '18 at 21:40
add a comme...
No Swipe Back when hiding Navigation Bar in UINavigationController
...a controller in the UINavigationController stack is what is causing the EXC_BAD_ACCESS errors.
Full Solution
First, add this class to your project:
class InteractivePopRecognizer: NSObject, UIGestureRecognizerDelegate {
var navigationController: UINavigationController
init(controller: U...
Error to run Android Studio
...l went right the answer should be something like this:
java version "1.8.0_91"
Java(TM) SE Runtime Environment (build 1.8.0_91-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.91-b14, mixed mode)
Check what compiler is used
javac -version
It should show something like this
javac 1.8.0_91
Fi...
What is the difference between a field and a property?
...It is private to your class and stores the actual data.
private string _myField;
// this is a property. When accessed it uses the underlying field,
// but only exposes the contract, which will not be affected by the underlying field
public string MyProperty
{
get
...