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What is the colon operator in Ruby?
..." # false
:foo.equal? :foo # true
This makes comparing two symbols really fast (since only a pointer comparison is involved, as opposed to comparing all the characters like you would in a string), plus you won't have a zillion copies of the same symbol floating about.
Also, unlike strings, sy...
Django templates: verbose version of a choice
... (universal), though - unless you know a way to iterate in a template over all get_FOO_display methods of a model object :) I'm a bit too lazy for writing non-generic templates ;) Moreover, the docs say it's a model instance's method. Therefore it'd have to be a model form bound to an existing obj...
Are parallel calls to send/recv on the same socket valid?
...tions, so assuming you're talking about POSIX send/recv then yes, you can call them simultaneously from multiple threads and things will work.
This doesn't necessarily mean that they'll be executed in parallel -- in the case of multiple sends, the second will likely block until the first completes....
When should I use C++14 automatic return type deduction?
...tatement boundaries we make types explicit, within expressions they are usually implicit but we can make them explicit with casts". C++11 and C++1y introduce type deduction tools so that you can leave out the type in new places.
Sorry, but you're not going to solve this up front by making general r...
What is the difference between the states selected, checked and activated in Android?
...
The difference between Checked and Activated is actually quite interesting. Even the Google documentation is apologetic (emphasis below added):
... For example, in a list view with single or multiple selection
enabled, the views in the current selection set are activate...
What does 'predicate' mean in the context of computer science? [duplicate]
...e(arg), here Java predicate interface --> docs.oracle.com/javase/8/docs/api/java/util/function/…
– Hernán Eche
Oct 7 '15 at 18:40
...
Copy data into another table
...the column list for newTable is optional if you are specifying a value for all columns and selecting columns in the same order as newTable's schema):
INSERT INTO newTable (col1, col2, col3)
SELECT column1, column2, column3
FROM oldTable
...
How to display the default iOS 6 share action sheet with available share options?
...he UIActivityViewController stated in the other answer makes this trivial. All you have to do is specify the text/image/URL that you want to share and present the activity view controller modally and iOS will automatically display all applicable sharing services. Examples:
Objective-C
- (void)shar...
Why does this Java code compile?
...+ 1 is illegal because b is an illegal forward reference to b. You can actually fix this by writing int b = this.b + 1, which compiles without complaints.
For local variables, int d = d + 1 is illegal because d is not initialized before use. This is not the case for fields, which are always default...
Can mustache iterate a top-level array?
...he');
var view = {test: 'div content', multiple : ['foo', 'bar'], multiple_2 : ['hello', 'world']};
var template = '<div>{{test}}</div><ul>{{#multiple}}<li>{{.}}</li>{{/multiple}}</ul><ul>{{#multiple_2}}<li>{{.}}</li>{{/multiple_2}}</ul>';...