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How to understand nil vs. empty vs. blank in Ruby
...used on strings, arrays and hashes and returns true if:
String length == 0
Array length == 0
Hash length == 0
Running .empty? on something that is nil will throw a NoMethodError.
That is where .blank? comes in. It is implemented by Rails and will operate on any object as well as work like .empt...
What do 'lazy' and 'greedy' mean in the context of regular expressions?
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Mibac
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answered Feb 20 '10 at 6:22
SampsonSampson
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Is there shorthand for returning a default value if None in Python? [duplicate]
...s also returns "default" if x is any falsy value, including an empty list, 0, empty string, or even datetime.time(0) (midnight).
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Is there a “do … while” loop in Ruby?
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How to set timer in android?
...n extends Activity {
TextView text, text2, text3;
long starttime = 0;
//this posts a message to the main thread from our timertask
//and updates the textfield
final Handler h = new Handler(new Callback() {
@Override
public boolean handleMessage(Message msg) {
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What does jquery $ actually return?
...et like an
array or access individual elements
via the indexer ($(sel)[0] for
example). More importantly, you can
also apply jQuery functions against
all the selected elements.
About returning nothing:
Does it always return an array? Does it return null?
You always get the same thi...
jQuery callback for multiple ajax calls
...tions) options = {};
numRequestToComplete = options.numRequest || 0;
requestsCompleted = options.requestsCompleted || 0;
callBacks = [];
var fireCallbacks = function() {
alert("we're all complete");
for (var i = 0; i < callBacks.length; i++...
How to iterate over values of an Enum having flags?
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edited Nov 13 '10 at 6:33
answered Nov 13 '10 at 6:26
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what exactly is device pixel ratio?
...solution is double the logical linear resolution.
Physical resolution: 960 x 640
Logical resolution: 480 x 320
The formula is:
Where:
is the physical linear resolution
and:
is the logical linear resolution
Other devices report different device pixel ratios, including non-integer ones. ...
Using SSH keys inside docker container
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