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What does “=>” mean in PHP?
...Note that this can be used for numerically indexed arrays too.
Example:
$foo = array('car', 'truck', 'van', 'bike', 'rickshaw');
foreach ($foo as $i => $type) {
echo "{$i}: {$type}\n";
}
// prints:
// 0: car
// 1: truck
// 2: van
// 3: bike
// 4: rickshaw
...
Why check both isset() and !empty()
...
This is completely redundant. empty is more or less shorthand for !isset($foo) || !$foo, and !empty is analogous to isset($foo) && $foo. I.e. empty does the reverse thing of isset plus an additional check for the truthiness of a value.
Or in other words, empty is the same as !$foo, but d...
'AND' vs '&&' as operator
...
If you use AND and OR, you'll eventually get tripped up by something like this:
$this_one = true;
$that = false;
$truthiness = $this_one and $that;
Want to guess what $truthiness equals?
If you said false... bzzzt, sorry, wrong!
$truthiness above has the ...
In Node.js, how do I “include” functions from my other files?
Let's say I have a file called app.js. Pretty simple:
26 Answers
26
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Release generating .pdb files, why?
...ase" build by anything other than address-level debugging. Optimizations really do a number on your code, making it very difficult to find the culprit if something goes wrong (say, an exception is thrown). Even setting breakpoints is extremely difficult, because lines of source code cannot be matche...
Java: Instanceof and Generics
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The error message says it all. At runtime, the type is gone, there is no way to check for it.
You could catch it by making a factory for your object like this:
public static <T> MyObject<T> createMyObject(Class<T> type) {
retu...
How do I tell if a regular file does not exist in Bash?
... The unary operator -z tests for a null string, while -n or no operator at all returns True if a string is not empty. ~ ibm.com/developerworks/library/l-bash-test/index.html
– BlueCacti
May 5 '14 at 11:06
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How to use XPath in Python?
... node set size"
sys.exit(1)
if res[0].name != "doc" or res[1].name != "foo":
print "xpath query: wrong node set value"
sys.exit(1)
doc.freeDoc()
ctxt.xpathFreeContext()
Sample of ElementTree XPath Use
from elementtree.ElementTree import ElementTree
mydoc = ElementTree(file='tst.xml'...
It is more efficient to use if-return-return or if-else-return?
...the if condition is false anyway.
Note that Python supports a syntax that allows you to use only one return statement in your case:
return A+1 if A > B else A-1
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What is the difference between bindParam and bindValue?
...value, if any, of their associated parameter markers
Example:
$value = 'foo';
$s = $dbh->prepare('SELECT name FROM bar WHERE baz = :baz');
$s->bindParam(':baz', $value); // use bindParam to bind the variable
$value = 'foobarbaz';
$s->execute(); // executed with WHERE baz = 'foobarbaz'
...