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Do I set properties to nil in dealloc when using ARC?

... must behave correctly if you pass it a nil value) and sometimes watch the order of deallocation. – Sulthan Mar 7 '12 at 21:23 7 ...
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How can I get nth element from a list?

...6 | `- 7 We can now access the elements of the tree in depth-first order: > tree ^? element 0 Just 1 > tree ^? element 1 Just 2 > tree ^? element 2 Just 4 > tree ^? element 3 Just 5 > tree ^? element 4 Just 3 > tree ^? element 5 Just 6 > tree ^? element 6 Just 7 We ca...
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Accessing class variables from a list comprehension in the class definition

...[i for i in range(1) for j in range(x)] This design decision was made in order to throw an error at genexp creation time instead of iteration time when creating the outermost iterable of a generator expression throws an error, or when the outermost iterable turns out not to be iterable. Comprehens...
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How does type Dynamic work and how to use it?

... If you use do checks at runtime, you have to do the parameter checking in order to dispatch correctly to the right code path. That shouldn't be more overhead than any other parameter checking in your application has. If you make use of reflection, you get obviously more overhead but you have to mea...
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Strings as Primary Keys in SQL Database [closed]

... a primary key is that because the index is constantly put into sequential order, when a new key is created that would be in the middle of the order the index has to be resequenced... if you use an auto number integer, the new key is just added to the end of the index. ...
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How to detect if a script is being sourced

...ipt or on the line after the shebang (which, if used, should be for ksh in order for it to work under the most circumstances). share | improve this answer | follow ...
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Selecting multiple columns in a pandas dataframe

...mns, like df.ix[0, 'Col1':'Col5']. That gets all columns that happen to be ordered between Col1 and Col5 in the df.columns array. It is incorrect to say that ix indexes rows. That is just its most basic use. It also supports much more indexing than that. So, ix is perfectly general for this question...
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Git cherry pick vs rebase

...nto it. Tries to apply each of the saved commits (as if with git apply) in order. In our toy example it's just one commit, C3. Let's say its application will produce a commit C3'. If all went well, the "experiment" reference is updated to point to the commit resulted from applying the last saved com...
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Generating a PNG with matplotlib when DISPLAY is undefined

... This works great, without the restrictions on the order used to import matplotlib and other libraries. – PabTorre Sep 5 '17 at 15:40 ...
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Git: How to return from 'detached HEAD' state

... warning: unable to unlink web/sites/default/default.settings.php: Permission denied ... other warnings ... Note: checking out '1.87.1'. You are in 'detached HEAD' state. You can look around, make experimental changes and commit them, and you can discard any commits you make in this st...