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List comprehension in Ruby
...
If you really want to, you can create an Array#comprehend method like this:
class Array
def comprehend(&block)
return self if block.nil?
self.collect(&block).compact
end
end
some_array = [1, 2, 3, 4, 5, 6]
new_ar...
Java: notify() vs. notifyAll() all over again
If one Googles for "difference between notify() and notifyAll() " then a lot of explanations will pop up (leaving apart the javadoc paragraphs). It all boils down to the number of waiting threads being waken up: one in notify() and all in notifyAll() .
...
Finding all possible permutations of a given string in python
I have a string. I want to generate all permutations from that string, by changing the order of characters in it. For example, say:
...
Use of Application.DoEvents()
... There's been an enormous amount of backlash against it, but nobody ever really explains why it is "bad". The same kind of wisdom as "don't mutate a struct". Erm, why does the runtime and the language supports mutating a struct if that's so bad? Same reason: you shoot yourself in the foot if you ...
How to check that a string is an int, but not a double, etc.?
... (ctype_digit($testcase)) {
echo "The string $testcase consists of all digits.\n";
} else {
echo "The string $testcase does not consist of all digits.\n";
}
}
?>
The above example will output:
The string 1820.20 does not consist of all digits.
The string 10002 consists...
How to increase font size in the Xcode editor?
... for:
Plain text
Comments
Documentation Comments
.
.
.
Select any or all items from the source editor list and the name and size of the font for
that particular text will show up in the 'Font' window below the 'Source Editor' window.
(If you happen to skip highlighting one of these, you will b...
INSERT IF NOT EXISTS ELSE UPDATE?
...ement case the statement would set it to NULL and then a fresh ID would be allocated.
This approach can also be used if you want to leave particular field values alone if the row in the replacement case but set the field to NULL in the insert case.
For example, assuming you want to leave Seen alon...
Detect all changes to a (immediately) using JQuery
...uery code catches immediate changes to any element, and should work across all browsers:
$('.myElements').each(function() {
var elem = $(this);
// Save current value of element
elem.data('oldVal', elem.val());
// Look for changes in the value
elem.bind("propertychange change click...
What is “2's Complement”?
...lement.
To understand, you have to think of the numbers in binary.
It basically says,
for zero, use all 0's.
for positive integers, start counting up, with a maximum of 2(number of bits - 1)-1.
for negative integers, do exactly the same thing, but switch the role of 0's and 1's (so instead of start...
Get size of all tables in database
... i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN
sys.allocation_units a ON p.partition_id = a.container_id
LEFT OUTER JOIN
sys.schemas s ON t.schema_id = s.schema_id
WHERE
t.NAME NOT LIKE 'dt%'
AND t.is_ms_shipped = 0
AND i.OBJECT_ID > 255
GROUP BY
t...