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Why do people write the #!/usr/bin/env python shebang on the first line of a Python script?
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using env gives maximum flexibility in that the user can select the interpreter to use by changing the PATH. Often this flexibility is not required though and the downside is that linux for example can't use the script name for the name of the process in ps and reverts to "python"....
Are loops really faster in reverse?
...it behind the curtain. The utmost overkill is to add options to forEach to select the looping algorithm.]
Moreover, also for low level languages, the best practice is to use some smart library function for complex, looped operations if it is possible.
Those libraries can also put things (multi-th...
Python: Checking if a 'Dictionary' is empty doesn't seem to work
...e for statement. As a result, your code will process only one, arbitrarily selected key, if a key exists. If a key does not exist, the function will return None, which will be cast to boolean False. Ouch! All the empty dictionaries will be classified as false-nagatives.
If the dictionary is not emp...
How can a windows service programmatically restart itself?
...location is in the services panel, right click the service in question and select properties, then choose recovery tab.
– James Michael Hare
Jul 7 '11 at 14:35
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Why JavaScript rather than a standard browser virtual machine?
...loping fast.
JavaScript is an ugly language, but through careful use of a selective subset of features, and support from suitable object libraries, it can generally be made fairly tolerable. It seems incremental, practical additions to JavaScript are the only way web scripting is likely to move on....
Finding a branch point with Git?
...ed from master):
or here (as viewed from topic):
in both cases, I've selected the commit that is B in my graph. Once you click on it, its full SHA is presented in a text input field just below the graph.
2. visually, but from the terminal:
git log --graph --oneline --all
(Edit/side-note:...
How to list of all the tables defined for the database when using active record?
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Don't know about active record, but here's a simple query:
select table_name
from INFORMATION_SCHEMA.Tables
where TABLE_TYPE = 'BASE TABLE'
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What are the main performance differences between varchar and nvarchar SQL Server data types?
... AND ([URLa] IS NULL OR [URLu] IS NULL))
);
In this model you only SELECT from the [URL] computed column. For inserting and updating, you determine which field to use by seeing if converting alters the incoming value, which has to be of NVARCHAR type:
INSERT INTO TableName (..., URLa, URLu)...
What is the difference between inversedBy and mappedBy?
...at doctrine can now safely use JOIN SQL statements instead of two separate SELECT statements. Without mappedBy, the doctrine engine would not know from the JOIN statement it will create what variable in the class 'Task' to put the category information.
Hope this explains it a bit better.
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Switch statement fallthrough in C#?
...# had not yet added any "soft" keywords (like 'yield', 'var', 'from', and 'select'), so they had three real options: 1) make 'fallthrough' a hard keyword (you cant use it as a variable name), 2) write code necessary to support such an soft keyword, 3) use already reserved keywords. #1 was a big issu...