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What is the best way to implement nested dictionaries?

I have a data structure which essentially amounts to a nested dictionary. Let's say it looks like this: 21 Answers ...
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Python memoising/deferred lookup property decorator

...nce, but they're a real bottleneck to calculate that first time and only really accessed for special cases. Hence they can also be cached after they've been retrieved from the database (this therefore fits the definition of memoisation where the input is simply "no input"). ...
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Can I install Python windows packages into virtualenvs?

Virtualenv is great: it lets me keep a number of distinct Python installations so that different projects' dependencies aren't all thrown together into a common pile. ...
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MySQL, Check if a column exists in a table with SQL

...pecific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception. ...
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How to access and test an internal (non-exports) function in a node.js module?

... This should absolutely be the top answer. It does not require rewriting all existing modules with NODE_ENV specific exports, nor does it involve reading in the module as text. – Adam Yost Jul 22 '15 at 16:00 ...
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Get the latest record from mongodb collection

...1 means order opposite of the one that records are inserted in. Edit: For all the downvoters, above is a Mongoose syntax, mongo CLI syntax is: db.collectionName.find({}).sort({$natural:-1}).limit(1) share | ...
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Useful code which uses reduce()? [closed]

...found for it besides + and * were with and and or, but now we have any and all to replace those cases. foldl and foldr do come up in Scheme a lot... Here's some cute usages: Flatten a list Goal: turn [[1, 2, 3], [4, 5], [6, 7, 8]] into [1, 2, 3, 4, 5, 6, 7, 8]. reduce(list.__add__, [[1, 2, 3]...
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What is the instanceof operator in JavaScript?

...ce p inherits from Person.prototype. Per the OP's request I've added a small example with some sample code and an explanation. When you declare a variable you give it a specific type. For instance: int i; float f; Customer c; The above show you some variables, namely i, f, and c. The type...
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Any way to make a WPF textblock selectable?

How to allow TextBlock 's text to be selectable? 15 Answers 15 ...
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How to concatenate properties from multiple JavaScript objects

...n Javascript. The Object.assign() method is used to copy the values of all enumerable own properties from one or more source objects to a target object. It will return the target object. MDN documentation on Object.assign() var o1 = { a: 1 }; var o2 = { b: 2 }; var o3 = { c: 3 }; var...