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JavaScript check if variable exists (is defined/initialized)
...lem.trim()) {
///
Also, these checks are for values only, as objects and arrays work differently in Javascript, empty array [] and empty object {} are always true.
I create the image below to show a quick brief of the answer:
...
Changing CSS Values with Javascript
...ve the stylesheets via document.styleSheets. This will actually return an array of all the stylesheets in your page, but you can tell which one you are on via the document.styleSheets[styleIndex].href property. Once you have found the stylesheet you want to edit, you need to get the array of rules...
passing 2 $index values within nested ng-repeat
...ex, but I needed to pass in BOTH $index values. I tried putting them in an array and it worked :)
– Tules
Mar 6 '13 at 21:26
16
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Which is more preferable to use: lambda functions or nested functions ('def')?
...r Python, rather than a true guiding principal. Consider the very-powerful array comprehensions in Python. They are functionally equivalent to the map and filter functions:
[e for e in some_array if some_condition(e)]
filter(some_array, some_condition)
lambda and def are the same.
It's a matter ...
How can I pad a value with leading zeros?
...idth -= number.toString().length;
if ( width > 0 )
{
return new Array( width + (/\./.test( number ) ? 2 : 1) ).join( '0' ) + number;
}
return number + ""; // always return a string
}
you could bake this into a library if you want to conserve namespace or whatever. Like with jQuery'...
Accessing outside variable using anonymous function as params
...n fetch($query,$func) {
$query = mysql_query($query);
$retVal = array();
while($r = mysql_fetch_assoc($query)) {
$retVal[] = $r;
}
$func($retVal);
}
This way you would call $func only once and re-process the array once fetched?
Not sure about the performance even tho...
map vs. hash_map in C++
..._hashtable_node<value_type> node;
// member data is buckets array(node* array)
std::vector<node*> buckets;
size_type num_elements;
public:
// insert only unique value
std::pair<iterator, bool> insert_unique(const value_type&...
base64 encoded images in email signatures
... the same problem to include QR image/png in email. The QR image is a byte array which is generated using ZXing. We do not want to save it to a file because saving/reading from a file is too expensive (slow). So both of the answers above do not work for me. Here's what I did to solve this problem:
...
mysqli or PDO - what are the pros and cons? [closed]
...r as representations of records which would otherwise be read-write assoc. arrays, this is acceptable. Furthermore it permits easier type checking as records float through the system.
– Dan Lugg
Jul 16 '11 at 0:50
...
What does [object Object] mean?
...ript!
Function objects:
stringify(function (){}) -> [object Function]
Array objects:
stringify([]) -> [object Array]
RegExp objects
stringify(/x/) -> [object RegExp]
Date objects
stringify(new Date) -> [object Date]
… several more …
and Object objects!
stringify({}) -> [object O...