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Difference between Observer, Pub/Sub, and Data Binding
...hat is the difference between the Observer Pattern , Publish/Subscribe , and Data Binding ?
4 Answers
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What is meant by 'first class object'?
...them
in data structures, passing them as
arguments to other functions, and
returning them as the values of other
functions.
This page also illustrates it beautifully:
Really, just like any other variable
A function is an instance of the Object type
A function can have properties and...
How to add custom validation to an AngularJS form?
I have a form with input fields and validation setup by adding the required attributes and such. But for some fields I need to do some extra validation. How would I "tap in" to the validation that FormController controls?
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Faster way to develop and test print stylesheets (avoid print preview every time)?
...a page in print mode.
To view a page in print mode:
1. Open the Command Menu. (tl;dr Cmd+Shift+P (Mac) or Ctrl+Shift+P (Windows, Linux))
2. Start typing Rendering and select Show Rendering.
3. For the Emulate CSS Media dropdown, select print.
UPDATE 29/02/2016
The DevTools docs h...
Why does Git treat this text file as a binary file?
...most but not completely not wrong. Git did have inspected the actual files and have seen 'funny' characters there. However it does not "think" UTF-16 is binary. It is binary, because text is defined as ASCII-based (that's the only thing the built-in diff will give usable results for) and UTF-16 is n...
Does this app use the Advertising Identifier (IDFA)? - AdMob 6.8.0
I'm currently uploading my App to the App Store and Apple is asking me if this app users IDFA. I'm using the latest Admob SDK or 6.8.0 and I don't know if it uses IDFA or not, and if it does which check boxes should I hit X.X
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How do I use the conditional operator (? :) in Ruby?
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It is the ternary operator, and it works like in C (the parenthesis are not required). It's an expression that works like:
if_this_is_a_true_value ? then_the_result_is_this : else_it_is_this
However, in Ruby, if is also an expression so: if a then b ...
Surrogate vs. natural/business keys [closed]
...
Both. Have your cake and eat it.
Remember there is nothing special about a primary key, except that it is labelled as such. It is nothing more than a NOT NULL UNIQUE constraint, and a table can have more than one.
If you use a surrogate key, y...
what does -webkit-transform: translate3d(0,0,0); exactly do? Apply to body?
...rocessing unit
(GPU) to make pixels fly. Web applications, on the other hand, run in
the context of the browser, which lets the software do most (if not
all) of the rendering, resulting in less horsepower for transitions.
But the Web has been catching up, and most browser vendors now provide...
HTTP GET with request body
...ther words, any HTTP request message is allowed to contain a message body, and thus must parse messages with that in mind. Server semantics for GET, however, are restricted such that a body, if any, has no semantic meaning to the request. The requirements on parsing are separate from the requirement...