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What is the difference between a weak reference and an unowned reference?
...a.k.a. they don't increase the retain count in order to prevent ARC from deallocating the referred object).
But why two keywords? This distinction has to do with the fact that Optional types are built-in the Swift language. Long story short about them: optional types offer memory safety (this works ...
How can I compare two dates in PHP?
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If all your dates are posterior to the 1st of January of 1970, you could use something like:
$today = date("Y-m-d");
$expire = $row->expireDate; //from database
$today_time = strtotime($today);
$expire_time = strtotime($exp...
How to create a hash or dictionary object in JavaScript [duplicate]
...sed instead of simply using Object. It is supported by current versions of all major browsers.
Maps do not support the [subscript] notation used by Objects. That syntax implicitly casts the subscript value to a primitive string or symbol. Maps support any values as keys, so you must use the methods...
Python pip install fails: invalid command egg_info
I find that recently often when I try to install a Python package using pip , I get the error(s) below.
15 Answers
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Currency formatting in Python
...ting.
>>> import locale
>>> locale.setlocale( locale.LC_ALL, '' )
'English_United States.1252'
>>> locale.currency( 188518982.18 )
'$188518982.18'
>>> locale.currency( 188518982.18, grouping=True )
'$188,518,982.18'
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jQuery: Best practice to populate drop down?
The example I see posted all of the time seems like it's suboptimal, because it involves concatenating strings, which seems so not jQuery. It usually looks like this:
...
How to convert a string to lower or upper case in Ruby
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You can find out all the methods available on a String by opening irb and running:
"MyString".methods.sort
And for a list of the methods available for strings in particular:
"MyString".own_methods.sort
I use this to find out new and int...
get the latest fragment in backstack
...gment in the back stack twice, you can't retrieve a specific fragment when all you have is the index or backstackentry entity.
– Justin
May 29 '14 at 15:54
14
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How can I avoid Java code in JSP files, using JSP 2?
...ance/composition.
Debuggability: if scriptlet throws an exception halfway, all you get is a blank page.
Testability: scriptlets are not unit-testable.
Maintainability: per saldo more time is needed to maintain mingled/cluttered/duplicated code logic.
Sun Oracle itself also recommends in the JSP co...
Selecting/excluding sets of columns in pandas [duplicate]
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@3kstc you can use df1.iloc[:, [-1]] this will select all rows, last column.
– Kocur4d
Apr 25 '18 at 10:16
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