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How do Google+ +1 widgets break out of their iframe?
...unning within the context of your website and therefore is not constrained by the Origin Inheritance Rules for iframes. Therefore this JavaScript widget can set whatever DOM events it wants on the parent site even though it appears to be just a simple iframe.
Another thing, why is Google using an...
PSQLException: current transaction is aborted, commands ignored until end of transaction block
...ause you are using a broken transaction to do additional work. PostgreSQL by default stops you from doing this.
I'm using: PostgreSQL 9.1.6 on x86_64-redhat-linux-gnu, compiled by gcc (GCC) 4.7.2 20120921 (Red Hat 4.7.2-2), 64-bit".
My PostgreSQL driver is: postgresql-9.2-1000.jdbc4.jar
Using Java ...
Overriding fields or properties in subclasses
...
Of the three solutions only Option 1 is polymorphic.
Fields by themselves cannot be overridden. Which is exactly why Option 2 returns the new keyword warning.
The solution to the warning is not to append the “new” keyword, but to implement Option 1.
If you need your field to ...
Sass calculate percent minus px
...
You can always use a fall back option by adding width: 22% at above all widths with calc
– Hengjie
Sep 3 '13 at 6:14
1
...
Change auto increment starting number?
...ment value, and the change will be applied instantly.
You can verify this by issuing a SHOW CREATE TABLE t statement. You should see:
> SHOW CREATE TABLE t \G
*************************** 1. row ***************************
Table: t
Create Table: CREATE TABLE `t` (
...
) ENGINE=InnoDB AUTO...
What is lexical scope?
... access its outer levels.
There is another way, called dynamic scope used by the first implementation of Lisp, again in a C-like syntax:
void fun()
{
printf("%d", x);
}
void dummy1()
{
int x = 5;
fun();
}
void dummy2()
{
int x = 10;
fun();
}
Here fun can either access x i...
Using Pylint with Django
...
Do not disable or weaken Pylint functionality by adding ignores or generated-members.
Use an actively developed Pylint plugin that understands Django.
This Pylint plugin for Django works quite well:
pip install pylint-django
and when running pylint add the following f...
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
...nnection refused
I'm quoting from this answer which also contains a step-by-step MySQL+JDBC tutorial:
If you get a SQLException: Connection refused or Connection timed out or a MySQL specific CommunicationsException:
Communications link failure, then it means that the DB isn't reachable at ...
Callback functions in C++
...d why to use them(!)
A callback is a callable (see further down) accepted by a class or function, used to customize the current logic depending on that callback.
One reason to use callbacks is to write generic code which is independant from the logic in the called function and can be reused with d...
What are allowed characters in cookies?
...to be OK in browsers I've got here; where are you having trouble with it?
By implication of the above:
= is legal to include, but potentially ambiguous. Browsers always split the name and value on the first = symbol in the string, so in practice you can put an = symbol in the VALUE but not the NA...