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Determining type of an object in ruby
...rmally type checking is not done in Ruby, but instead objects are assessed based on their ability to respond to particular methods, commonly called "Duck typing". In other words, if it responds to the methods you want, there's no reason to be particular about the type.
For example, object.is_a?(Str...
How to install multiple python packages at once using pip
...files for their general layout and syntax - note that you can generate one based on current environment / site-packages with pip freeze if you want a quick example - e.g. (based on having installed wsgiref and boto in a clean virtualenv):
$ pip freeze
boto==2.3.0
wsgiref==0.1.2
...
Android Gallery on Android 4.4 (KitKat) returns different URI for Intent.ACTION_GET_CONTENT
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Based on KitKat docs (developer.android.com/about/versions/…) this may not be what the OP needs unless he does intent to use/edit documents that are owned by the other application(s). If the OP wants a copy or to do things...
How to make the first option of selected with jQuery
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It works, but it's based on 1st element value, if 1st element contains empty value, it will select nearest element WITH value
– evilReiko
Mar 1 '11 at 12:37
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What is a Manifest in Scala and when do you need it?
...tail.
One common use of Manifests is to have your code behave differently based on the static type of a collection. For example, what if you wanted to treat a List[String] differently from other types of a List:
def foo[T](x: List[T])(implicit m: Manifest[T]) = {
if (m <:< manifest[Str...
Format Float to n decimal places
... rounding is going to be chaotic and unpredictable any time you mix binary-based floating-point values with base-10 arithmetic. I'm pretty sure it cannot be done. The basic problem is that a value like 1.105 cannot be represented exactly in floating point. The floating point value is going to be som...
In absence of preprocessor macros, is there a way to define practical scheme specific flags at proje
...nd keep them up to date for different targets etc. Also, in our mixed codebase, we didn't want to make remember to set our flags appropriately all the time for each language.
For ours, we declared a file in ObjC
PreProcessorMacros.h
extern BOOL const DEBUG_BUILD;
In the .m
PreProcessorMacros....
Good examples of MVVM Template
...pproach, which is not quite classic MVVM, can be summarized as follows:
A base class for a dialog ViewModel that exposes commands for commit and cancel actions, an event to lets the view know that a dialog is ready to be closed, and whatever else you will need in all of your dialogs.
A generic vi...
ES6 class variable alternatives
...eally have classes. Even with ES6 we're looking at an object- or prototype-based language rather than a class-based language. In any function X () {}, X.prototype.constructor points back to X.
When the new operator is used on X, a new object is created inheriting X.prototype. Any undefined properti...
Get user profile picture by Id
I'm now working on a web application which is mostly based of facebook graph api.
I hold some data about users - actually , the possible public data available - such as name and id.
I also know that a profile picture is a part of the public data, and I wondered how I'll be able to get a direct link ...