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Type-juggling and (strict) greater/lesser-than comparisons in PHP
...RUE); // bool(false)
Extra: PHP's < operator is not trichotomous, i.e. all of $a < $b, $b < $a and $a == $b can be false (Example same as for <= not being total).
Extra: PHP's < operator can be circular, i.e. it is possible that $a < $b, $b < $c and $c < $a:
var_dump(INF &...
Difference between natural join and inner join
...aspect of a natural join. The things you need to know are (A) it automatically joins on fields of the same name and (B) it will f*** up your s*** when you least expect it. In my world, using a natural join is grounds for dismissal.
– user565869
Jan 6 '14 at 1...
Storing Images in PostgreSQL
...we see that image sizes, and number of images, are growing and growing, in all applications...
We need some distinction between "original image" and "processed image", like thumbnail.
As Jcoby's answer says, there are two options, then, I recommend:
use blob (Binary Large OBject): for original imag...
Why should I avoid multiple inheritance in C++?
...
Multiple inheritance (abbreviated as MI) smells, which means that usually, it was done for bad reasons, and it will blow back in the face of the maintainer.
Summary
Consider composition of features, instead of inheritance
Be wary of the Diamond of Dread
Consider inheritance of multiple interf...
Choosing between qplot() and ggplot() in ggplot2 [closed]
...I will use this
Of course, more complex plots require ggplot(), and I usually store data in data.frame, so in my experience, I rarely use qplot.
And it sounds good to always use ggplot(). While qplot saves typing, you lose a lot of functionalities.
...
AutoLayout with hidden UIViews?
...
Would be nice to give a small example of how stack view handles this.
– lostintranslation
Sep 9 '16 at 19:47
...
When do I use a dot, arrow, or double colon to refer to members of a class in C++?
...d for three different scenarios that are always well-defined. Knowing this allows you to immediately know quite a lot about a and b just by looking at a::b, a.b, or a->b, respectively, in any code you look at.
a::b is only used if b is a member of the class (or namespace) a. That is, in this c...
Split string based on a regular expression
...y in this case.
>>> str1.split()
['a', 'b', 'c', 'd']
If you really wanted regex you can use this ('\s' represents whitespace and it's clearer):
>>> re.split("\s+", str1)
['a', 'b', 'c', 'd']
or you can find all non-whitespace characters
>>> re.findall(r'\S+',str1)
...
How can I iterate over an enum?
... Two = 9,
Three = 4,
Last
};
This illustrates that an enum is not really meant to iterate through. The typical way to deal with an enum is to use it in a switch statement.
switch ( foo )
{
case One:
// ..
break;
case Two: // intentional fall-through
case Three:
...
How to use wait and notify in Java without IllegalMonitorStateException?
...
To be able to call notify() you need to synchronize on the same object.
synchronized (someObject) {
someObject.wait();
}
/* different thread / object */
synchronized (someObject) {
someObject.notify();
}
...