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How do I get the key at a specific index from a Dictionary in Swift?
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Iulian Onofrei
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answered Jul 8 '14 at 20:20
Mick MacCallumMick Mac...
Ruby: How to get the first character of a string
...ial # prints S
The other method mentioned here doesn't work on Ruby 1.8 (not that you should be using 1.8 anymore anyway!--but when this answer was posted it was still quite common):
puts 'Smith'[0] # prints 83
Of course, if you're not doing it on a regular basis, then defining the...
How to concatenate strings of a string field in a PostgreSQL 'group by' query?
...SELECT string_agg(actor_name, ', ' ORDER BY first_appearance)
PostgreSQL 8.4 or later:
PostgreSQL 8.4 (in 2009) introduced the aggregate function array_agg(expression) which concatenates the values into an array. Then array_to_string() can be used to give the desired result:
SELECT company_id, a...
mysql_config not found when installing mysqldb python interface
...eference:
https://github.com/JudgeGirl/Judge-sender/issues/4#issuecomment-186542797
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Which is faster: while(1) or while(2)?
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681
Both loops are infinite, but we can see which one takes more instructions/resources per iterati...
No secret option provided to Rack::Session::Cookie warning?
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86
This is a Rails bug, as the subclass is violating the superclass API contract.
The warn...
How to filter out files by extension in NERDTree?
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edited Apr 8 '11 at 23:45
answered Apr 8 '11 at 23:40
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How can a Javascript object refer to values in itself? [duplicate]
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8 Answers
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CSV in Python adding an extra carriage return, on Windows
...et newline='\n'
with open('output.csv', 'w', newline='\n', encoding='utf-8') as f:
writer = csv.writer(f)
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Python 2:
On Windows, always open your files in binary mode ("rb" or "wb"), before passing them to csv.reader or csv.writer.
Although the file is a text file, CSV is regarded...
What is the 'cls' variable used for in Python classes?
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The distinction between "self" and "cls" is defined in PEP 8 . As Adrien said, this is not a mandatory. It's a coding style. PEP 8 says:
Function and method arguments:
Always use self for the first argument to instance methods.
Always use cls for the first argument to class methods....