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How to manually expand a special variable (ex: ~ tilde) in bash

... +1 -- I was needing to expand ~$some_other_user and eval works fine when $HOME will not work because I don't need the current user home. – olivecoder Sep 10 '13 at 11:30 ...
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Differences between lodash and underscore [closed]

...Of"), while in older browsers they will not. Also, Underscore methods like _.clone preserve holes in arrays, while others like _.flatten don't. share | improve this answer | ...
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Python set to list

...k that you didn't overwrite list by accident: >>> assert list == __builtins__.list share | improve this answer | follow | ...
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What is the Java string pool and how is “s” different from new String(“s”)? [duplicate]

... a reference to an instance of class String, and is derived from a CONSTANT_String_info structure (§4.4.3) in the binary representation of a class or interface. The CONSTANT_String_info structure gives the sequence of Unicode code points constituting the string literal. The Java programming la...
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MongoDB Aggregation: How to get total records count?

...te(array( array('$match' => $document), array('$group' => array('_id' => '$book_id', 'date' => array('$max' => '$book_viewed'), 'views' => array('$sum' => 1))), array('$sort' => $sort), // get total, AND preserve the results array('$group' => array('_id' => nu...
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Retrieve only the queried element in an object array in MongoDB collection

...atched shapes element: db.test.find( {"shapes.color": "red"}, {_id: 0, shapes: {$elemMatch: {color: "red"}}}); Returns: {"shapes" : [{"shape": "circle", "color": "red"}]} In 2.2 you can also do this using the $ projection operator, where the $ in a projection object field name repre...
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Execute code when Django starts ONCE only?

...d executed once. urls.py from django.confs.urls.defaults import * from my_app import one_time_startup urlpatterns = ... one_time_startup() share | improve this answer | ...
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pandas three-way joining multiple dataframes on columns

...ve some common column, like name in your example, I'd do the following: df_final = reduce(lambda left,right: pd.merge(left,right,on='name'), dfs) That way, your code should work with whatever number of dataframes you want to merge. Edit August 1, 2016: For those using Python 3: reduce has been m...
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node.js equivalent of python's if __name__ == '__main__' [duplicate]

I'd like to check if my module is being included or run directly. How can I do this in node.js? 2 Answers ...
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What does Python's eval() do?

... command string and then have python run it as code. So for example: eval("__import__('os').remove('file')"). – BYS2 Feb 21 '12 at 19:24 ...