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Is object empty? [duplicate]
...Error)
isEmpty([]), // true
isEmpty({}), // true
isEmpty({length: 0, custom_property: []}), // true
isEmpty("Hello"), // false
isEmpty([1,2,3]), // false
isEmpty({test: 1}), // false
isEmpty({length: 3, custom_property: [1,2,3]}) // false
If you only need to handle ECMAScript5 browsers, you can u...
How do you get the length of a list in the JSF expression language?
...g addressed in a JSR245 maintenance release: blogs.sun.com/kchung/entry/jsr_245_mr_part_i (In terms of JEE specs, that'll be JEE6)
– McDowell
Sep 1 '09 at 11:46
...
How do I check if a variable exists?
...ar exists.
To check if an object has an attribute:
if hasattr(obj, 'attr_name'):
# obj.attr_name exists.
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Why is “import *” bad?
...citly imported ones, and possibly point to very different things. Defining __all__ in bar is often wise -- this states what will implicitly be imported - but still it's hard to trace where objects come from, without reading and parsing the bar module and following its imports. A network of import * ...
UITableView with fixed section headers
...ain table style but don't float buz
setting table style set to group.
[_tableView setBackgroundView:nil];
_tableView.backgroundColor = [UIColor whiteColor];
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Mixins vs. Traits
... answered Jan 26 '11 at 9:15
jk_jk_
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How do I make a request using HTTP basic authentication with PHP curl?
...
You want this:
curl_setopt($ch, CURLOPT_USERPWD, $username . ":" . $password);
Zend has a REST client and zend_http_client and I'm sure PEAR has some sort of wrapper.
But its easy enough to do on your own.
So the entire request might look ...
Why does parseInt yield NaN with Array#map?
...x parameter.
If you're using underscore you can do:
['10','1','100'].map(_.partial(parseInt, _, 10))
Or without underscore:
['10','1','100'].map(function(x) { return parseInt(x, 10); });
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Random record from MongoDB
... enable geospatial indexing on a collection:
db.docs.ensureIndex( { random_point: '2d' } )
To create a bunch of documents with random points on the X-axis:
for ( i = 0; i < 10; ++i ) {
db.docs.insert( { key: i, random_point: [Math.random(), 0] } );
}
Then you can get a random document f...
typeof !== “undefined” vs. != null
...gument, or as a global variable), I think the best way to do it is:
if (my_variable === undefined)
jQuery does it, so it's good enough for me :-)
Otherwise, you'll have to use typeof to avoid a ReferenceError.
If you expect undefined to be redefined, you could wrap your code like this:
(functi...