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String comparison in Python: is vs. == [duplicate]
...
For all built-in Python objects (like
strings, lists, dicts, functions,
etc.), if x is y, then x==y is also
True.
Not always. NaN is a counterexample. But usually, identity (is) implies equality (==). The converse is n...
Convert Unix timestamp to a date string
...ecognizes neither -d nor -r and provides no standard way in any command at all (that I know of) to format a Unix time from the command line (since POSIX Awk also lacks strftime()). (You can't use touch -t and ls because the former does not accept a time given as seconds since the Unix Epoch.)
Note...
'typeid' versus 'typeof' in C++
...perator which returns type identification information at run time. It basically returns a type_info object, which is equality-comparable with other type_info objects.
Note, that the only defined property of the returned type_info object has is its being equality- and non-equality-comparable, i.e. t...
What is the difference between “def” and “val” to define a function
...ion every time (new instance of Function1).
def even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = false
val even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = true
With def you can get new function on every call:
val test: () => Int = {
val r = util.Random.nextInt
...
What is a “translation unit” in C++
...
A translation unit is for all intents and purposes a file (.c/.cpp), after it's finished including all of the header files.
http://msdn.microsoft.com/en-us/library/bxss3ska%28VS.80%29.aspx
...
Dilemma: when to use Fragments vs Activities:
.... In the beginning this will not have any sense, but in time, you will actually be able to tell if you need Fragment or not.
There is a good practice I found very helpful for me. It occurred to me while I was trying to explain something to my daughter.
Namely, imagine a box which represents a sc...
How to log something in Rails in an independent log file?
...
If you want to change all the default logging for that specific model, you can simply use User.logger = Logger.new(STDOUT) or wherever you want to log to. In the same way, ActiveRecord::Base.logger = Logger.new(STDOUT) will change all the logging ...
Ternary Operator Similar To ?:
...or that we just defined:
object T { val condition = true
import Bool._
// yay!
val x = condition ? "yes" | "no"
}
Have fun ;)
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Use of def, val, and var in scala
...sed:
scala> something = 5 * 6
<console>:8: error: value something_= is not a member of object $iw
something = 5 * 6
^
When the class is defined like:
scala> class Person(val name: String, var age: Int)
defined class Person
and then instantiated with:
scala> def pe...
Disabling user selection in UIWebView
...mobile web documents
<style type="text/css">
* {
-webkit-touch-callout: none;
-webkit-user-select: none; /* Disable selection/copy in UIWebView */
}
</style>
Programmatically load the following Javascript code:
NSString * jsCallBack = @"window.getSelection().removeAllRanges()...
