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What is the purpose of willSet and didSet in Swift?

...ws conditional setting of an actual stored property //True model data var _test : Int = 0 var test : Int { get { return _test } set (aNewValue) { //I've contrived some condition on which this property can be set if (aNewValue != test) { _test = aNewV...
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What does $_ mean in PowerShell?

...ich is called $PSItem in Powershell 3 and newer. 1,2,3 | %{ write-host $_ } or 1,2,3 | %{ write-host $PSItem } For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable will contain the current value. ...
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How do I perform the SQL Join equivalent in MongoDB?

...ttps://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup From the docs: { $lookup: { from: <collection to join>, localField: <field from the input documents>, foreignField: <field from the documents of the "from" collection&gt...
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How to automatically remove trailing whitespace in Visual Studio 2008?

...r your macros. Private saved As Boolean = False Private Sub DocumentEvents_DocumentSaved(ByVal document As EnvDTE.Document) _ Handles DocumentEvents.DocumentSaved If Not saved Then Try DTE.Find.FindReplace(vsFindAction.vsFindActionRep...
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What's the difference between dist-packages and site-packages?

... manager into this location: /usr/lib/python2.7/dist-packages Since easy_install and pip are installed from the package manager, they also use dist-packages, but they put packages here: /usr/local/lib/python2.7/dist-packages From the Debian Python Wiki: dist-packages instead of site-packag...
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Any gotchas using unicode_literals in Python 2.6?

...ng: utf-8 name = 'helló wörld from two' one.py # encoding: utf-8 from __future__ import unicode_literals import two name = 'helló wörld from one' print name + two.name The output of running python one.py is: Traceback (most recent call last): File "one.py", line 5, in <module> ...
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What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?

... GCC has: -- Built-in Function: int __builtin_clz (unsigned int x) Returns the number of leading 0-bits in X, starting at the most significant bit position. If X is 0, the result is undefined. -- Built-in Function: int __builtin_clzl (unsigned long...
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Count the number occurrences of a character in a string

...quently, check out collections.Counter: from collections import Counter my_str = "Mary had a little lamb" counter = Counter(my_str) print counter['a'] share | improve this answer | ...
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How to change Rails 3 server default port in develoment?

..."rails" with Rails 3 gems installed from the root of your application. APP_PATH = File.expand_path('../../config/application', __FILE__) require File.expand_path('../../config/boot', __FILE__) # THIS IS NEW: require "rails/commands/server" module Rails class Server def default_options ...
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Disable button in jQuery

My page creates multiple buttons as id = 'rbutton_"+i+"' . Below is my code: 11 Answers ...