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How do you echo a 4-digit Unicode character in Bash?
...d like to add the Unicode skull and crossbones to my shell prompt (specifically the 'SKULL AND CROSSBONES' (U+2620)), but I can't figure out the magic incantation to make echo spit it, or any other, 4-digit Unicode character. Two-digit one's are easy. For example, echo -e "\x55", .
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List of special characters for SQL LIKE clause
What is the complete list of all special characters for a SQL (I'm interested in SQL Server but other's would be good too) LIKE clause?
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Multiple levels of 'collection.defaultdict' in Python
...ng specific that you need help with? When d[new_key] is accessed, it will call the lambda which will create a new defaultdict(int). And when d[existing_key][new_key2] is accessed, a new int will be created.
– interjay
Oct 11 '13 at 12:53
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How do I create a namespace package in Python?
In Python, a namespace package allows you to spread Python code among several projects. This is useful when you want to release related libraries as separate downloads. For example, with the directories Package-1 and Package-2 in PYTHONPATH ,
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Adding a cross-reference to a subheading or anchor in another page
... because it works across files, when section headings are changed, and for all builders that support cross-references.
RST, in General
The tools that convert RST files to HTML do not necessarily have a notion of collection. This is the case for instance if you rely on github to convert RST files ...
Are HLists nothing more than a convoluted way of writing tuples?
I am really interested in finding out where the differences are, and more generally, to identify canonical use cases where HLists cannot be used (or rather, don't yield any benefits over regular lists).
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MongoDB/NoSQL: Keeping Document Change History
... changes to one or more specific entities in a database. I've heard this called row versioning, a log table or a history table (I'm sure there are other names for it). There are a number of ways to approach it in an RDBMS--you can write all changes from all source tables to a single table (more of...
MongoDB Many-to-Many Association
... user document:
{name:"Joe"
,roles:["Admin","User","Engineer"]
}
To get all the Engineers, use:
db.things.find( { roles : "Engineer" } );
If you want to maintain the roles in separate documents then you can include the document's _id in the roles array instead of the name:
{name:"Joe"
,roles:...
Read-only and non-computed variable properties in Swift
...g in Objective-C. I have readonly properties, and they cannot be individually changed. However, using a specific method, the properties are changed in a logical way.
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Do I set properties to nil in dealloc when using ARC?
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Short answer: no, you do not have to nil out properties in dealloc under ARC.
Long answer: You should never nil out properties in dealloc, even in manual memory management.
In MRR, you should release your ivars. Nilling out properties means calling setters, which may invoke code that...